Comparing 2016 Amateur Extra class pool with
2012 Amateur Extra class pool
Removed questions: 131
New questions: 142
Updated questions: 60
Previous Total questions: 700
Total questions: 712
Subelement E1
COMMISSION'S RULES
Removed questions: 3
New questions: 5
Updated questions: 8
Total questions: 75
Section E1A
Operating Standards: frequency privileges; emission standards; automatic message forwarding; frequency sharing; stations aboard ships or aircraft
Removed questions: 1
New questions: 0
Updated questions: 3
Total questions: 14
REMOVED
Which of the following describes the rules for operation on the 60 meter band?
Working DX is not permitted
Operation is restricted to specific emission types and specific channels
Operation is restricted to LSB
All of these choices are correct
When using a transceiver that displays the carrier frequency of phone signals, which of the following displayed frequencies represents the highest frequency at which a properly adjusted USB emission will be totally within the band?
The exact upper band edge
300 Hz below the upper band edge
1 kHz below the upper band edge
3 kHz below the upper band edge
When using a transceiver that displays the carrier frequency of phone signals, which of the following displayed frequencies represents the lowest frequency at which a properly adjusted LSB emission will be totally within the band?
The exact lower band edge
300 Hz above the lower band edge
1 kHz above the lower band edge
3 kHz above the lower band edge
With your transceiver displaying the carrier frequency of phone signals, you hear a DX station's calling CQ on 14.349 MHz USB. Is it legal to return the call using upper sideband on the same frequency?
Yes, because the DX you were not the station calling CQinitiated the contact
Yes, because the displayed frequency is within the 20 meter band
No, my sidebandsNo, the sideband will extend beyond the band edge
No, USANo, U.S. stations are not permitted to use phone emissions above 14.340 MHz
With your transceiver displaying the carrier frequency of phone signals, you hear a DX station calling CQ on 3.601 MHz LSB. Is it legal to return the call using lower sideband on the same frequency?
Yes, because the DX station initiated the contact
Yes, because the displayed frequency is within the 75 meter phone band segment
No, my sidebandsNo, the sideband will extend beyond the edge of the phone band segment
No, USANo, U.S. stations are not permitted to use phone emissions below 3.610 MHz
What is the maximum power output permitted on the 60 meter band?
50 watts PEP effective radiated power relative to an isotropic radiator
50 watts PEP effective radiated power relative to a dipole
100 watts PEP effective radiated power relative to the gain of a half-wave dipole
100 watts PEP effective radiated power relative to an isotropic radiator
was E1B07
Where must the carrier frequency of a CW signal be set to comply with FCC rules for 60 meter operation?
At the lowest frequency of the channel
At the center frequency of the channel
At the highest frequency of the channel
On any frequency where the signal's sidebands are within the channel
What is the only Which amateur band whererequires transmission on specific channels rather than on a range of frequencies? is permitted?
12 meter band
17 meter band
30 meter band
60 meter band
If a station in a message forwarding system inadvertently forwards a message that is in violation of FCC rules, who is primarily accountable for the rules violation?
The control operator of the packet bulletin board station
The control operator of the originating station
The control operators of all the stations in the system
The control operators of all the stations in the system not authenticating the source from which they accept communications
What is the first action you should take if your digital message forwarding station inadvertently forwards a communication that violates FCC rules?
Discontinue forwarding the communication as soon as you become aware of it
Notify the originating station that the communication does not comply with FCC rules
Notify the nearest FCC Field Engineer's office
Discontinue forwarding all messages
If an amateur station is installed aboard a ship or aircraft, what condition must be met before the station is operated?
Its operation must be approved by the master of the ship or the pilot in command of the aircraft
The amateur station operator must agree to not not to transmit when the main radio of the ship or aircraft radios are is in use
It The amateur station must have a power supply that is completely independent of the main ship or aircraft power supply
Its The amateur operator must have an FCC Marine or Aircraft endorsement on his or her amateur license
What Which of the following describes authorization or licensing is required when operating an amateur station aboard a US-U.S.-registered vessel in international waters?
Any amateur license with an FCC Marine or Aircraft endorsement
Any FCC-issued amateur license or a reciprocal permit for an alien amateur licensee
Only General class or higher amateur licenses
An unrestricted Radiotelephone Operator Permit
With your transceiver displaying the carrier frequency of CW signals, you hear a DX station's CQ on 3.500 MHz. Is it legal to return the call using CW on the same frequency?
Yes, the DX station initiated the contact
Yes, the displayed frequency is within the 80 meter CW band segment
No, No, one of the sidebands fromof the CW signal will be out of the band.
No, USANo, U.S. stations are not permitted to use CW emissions below 3.525 MHz
Who must be in physical control of the station apparatus of an amateur station aboard any vessel or craft that is documented or registered in the United States?
Only a person with an FCC Marine Radio
Any person holding an FCC- issued amateur license or who is authorized for alien reciprocal operation
Only a person named in an amateur station license grant
Any person named in an amateur station license grant or a person holding an unrestricted Radiotelephone Operator Permit
was E1B05
What is the maximum bandwidth for a data emission on 60 meters?
60 Hz
170 Hz
1.5 kHz
2.8 kHz
Section E1B
Station restrictions and special operations: restrictions on station location; general operating restrictions;, spurious emissions, control operator reimbursement; antenna structure restrictions; RACES operations; national quiet zone
Removed questions: 0
New questions: 0
Updated questions: 2
Total questions: 11
Which of the following constitutes a spurious emission?
An amateur station transmission made at random without the proper call sign identification
A signal transmitted to prevent its detection by any station other than the intended recipient
Any transmitted bogus signal that unintentionally interferes with another licensed radio station
An emission outside its necessary bandwidth that can be reduced or eliminated without affecting the information transmitted
Which of the following factors might cause the physical location of an amateur station apparatus or antenna structure to be restricted?
The location is near an area of political conflict
The location is of geographical or horticultural importance
The location is in an ITU zoneZone designated for coordination with one or more foreign governments
The location is of environmental importance or significant in American history, architecture, or culture
Within what distance must an amateur station protect an FCC monitoring facility from harmful interference?
1 mile
3 miles
10 miles
30 miles
What must be done before placing an amateur station within an officially designated wilderness area or wildlife preserve, or an area listed in the National Register of Historical Places?
A proposal must be submitted to the National Park Service
A letter of intent must be filed with the National Audubon Society
An Environmental Assessment must be submitted to the FCC
A form FSD-15 must be submitted to the Department of the Interior
was E1F06
What is the National Radio Quiet Zone?
An area in Puerto Rico surrounding the AriceboArecibo Radio Telescope
An area in New Mexico surrounding the White Sands Test Area
An area surrounding the National Radio Astronomy Observatory
An area in Florida surrounding Cape Canaveral
Which of the following additional rules apply if you are installing an amateur station antenna at a site at or near a public use airport?
You may have to notify the Federal Aviation Administration and register it with the FCC as required by Part 17 of FCC rules
No special rules apply if your antenna structure will be less than 300 feet in height
You must file an Environmental Impact Statement with the EPA before construction begins
You must obtain a construction permit from the airport zoning authority
was E1B12
What is the highest modulation index permitted at the highest modulation frequency for angle modulation below 29.0 MHz??
.50.5
1.0
2.0
3.0
What limitations may the FCC place on an amateur station if its signal causes interference to domestic broadcast reception, assuming that the receiver(s)receivers involved are of good engineering design?
The amateur station must cease operation
The amateur station must cease operation on all frequencies below 30 MHz
The amateur station must cease operation on all frequencies above 30 MHz
The amateur station must avoid transmitting during certain hours on frequencies that cause the interference
Which amateur stations may be operated inunder RACES rules??
Only those club stations licensed to Amateur Extra class operators
Any FCC-licensed amateur station except a Technician class operator's station
Any FCC-licensed amateur station certified by the responsible civil defense organization for the area served
Any FCC-licensed amateur station participating in the Military AffiliateAuxiliary Radio System (MARS)
What frequencies are authorized to an amateur station participating inoperating under RACES rules??
All amateur service frequencies authorized to the control operator
Specific segments in the amateur service MF, HF, VHF and UHF bands
Specific local government channels
Military AffiliateAuxiliary Radio System (MARS) channels
What is the permitted mean power of any spurious emission relative to the mean power of the fundamental emission from a station transmitter or external RF amplifier installed after January 1, 2003, and transmitting on a frequency below 30 MHZ?
At least 43 dB below
At least 53 dB below
At least 63 dB below
At least 73 dB below
Section E1C
Station Control: Definitions and restrictions pertaining to local, automatic and remote control operation; control operator responsibilities for remote and automatically controlled stations; IARP and CEPT licenses; third party communications over automatically controlled stations
Removed questions: 1
New questions: 2
Updated questions: 1
Total questions: 13
REMOVED
When may an automatically controlled station retransmit third party communications?
Never
Only when transmitting RTTY or data emissions
When specifically agreed upon by the sending and receiving stations
When approved by the National Telecommunication and Information Administration
What is a remotely controlled station?
A station operated away from its regular home location
A station controlled by someone other than the licensee
A station operating under automatic control
A station controlled indirectly through a control link
What is meant by automatic control of a station?
The use of devices and procedures for control so that the control operator does not have to be present at a control point
A station operating with its output power controlled automatically
Remotely controlling a station's antenna pattern through a directional control link
The use of a control link between a control point and a locally controlled station
How do the control operator responsibilities of a station under automatic control differ from one under local control?
Under local control there is no control operator
Under automatic control the control operator is not required to be present at the control point
Under automatic control there is no control operator
Under local control a control operator is not required to be present at a control point
- NEW -
What is meant by IARP?
An international amateur radio permit that allows U.S. amateurs to operate in certain countries of the Americas
The internal amateur radio practices policy of the FCC
An indication of increased antenna reflected power
A forecast of intermittent aurora radio propagation
When may an automatically controlled station originate third party communications?
Never
Only when transmitting an RTTY or data emissions
When specifically agreed upon by the sending andor receiving stationstations
When approved by the National Telecommunication and Information Administration
Which of the following statements concerning remotely controlled amateur stations is true?
Only Extra Class operators may be the control operator of a remote station
A control operator need not be present at the control point
A control operator must be present at the control point
Repeater and auxiliary stations may not be remotely controlled
What is meant by local control?
Controlling a station through a local auxiliary link
Automatically manipulating local station controls
Direct manipulation of the transmitter by a control operator
Controlling a repeater using a portable handheld transceiver
What is the maximum permissible duration of a remotely controlled station's transmissions if its control link malfunctions?
30 seconds
3 minutes
5 minutes
10 minutes
Which of these ranges of frequencies areis available for an automatically controlled repeater operating below 30 MHz?
18.110 MHz - 18.168 MHz
24.940 MHz - 24.990 MHz
10.100 MHz - 10.150 MHz
29.500 MHz - 29.700 MHz
What types of amateur stations may automatically retransmit the radio signals of other amateur stations?
Only beacon, repeater or space stations
Only auxiliary, repeater or space stations
Only earth stations, repeater stations or model craft
Only auxiliary, beacon or space stations
was E1F02
Which of the following operating arrangements allows an FCC-licensed USU.S. citizen to operate in many European countries, and alien amateurs from many European countries to operate in the U.S.?US?
CEPT agreement
IARP agreement
ITU reciprocal license
All of these choices are correct
was E1F13
What types of communications may be transmitted to amateur stations in foreign countries?
Business-related messages for non-profit organizations
Messages intended for connection to users of the maritime satellite service
Communications incidental to the purpose of the amateur service and remarks of a personal nature
All of these choices are correct
- NEW -
Which of the following is required in order to operate in accordance with CEPT rules in foreign countries where permitted?
You must identify in the official language of the country in which you are operating
The U.S. embassy must approve of your operation
You must bring a copy of FCC Public Notice DA 11-221
You must append "/CEPT" to your call sign
Section E1D
Amateur Satellite servicesatellites: definitions and purpose; license requirements for space stations; available frequencies and bands; telecommand and telemetry operations; restrictions, and special provisions; notification requirements
Removed questions: 0
New questions: 1
Updated questions: 1
Total questions: 11
What is the definition of the term telemetry?
One-way transmission of measurements at a distance from the measuring instrument
Two-way radiotelephone transmissions in excess of 1000 feet
Two-way single channel transmissions of data
One-way transmission that initiates, modifies, or terminates the functions of a device at a distance
What is the amateur satellite service?
A radio navigation service using satellites for the purpose of self training, intercommunication and technical studies carried out by amateurs
A spacecraft launching service for amateur-built satellites
A radio communications service using amateur radio stations on satellites
A radio communications service using stations on Earth satellites for public service broadcast
What is a telecommand station in the amateur satellite service?
An amateur station located on the Earth's surface for communicationscommunication with other Earth stations by means of Earth satellites
An amateur station that transmits communications to initiate, modify or terminate functions of a space station
An amateur station located more than 50 km above the Earth's surface
An amateur station that transmits telemetry consisting of measurements of upper atmosphere data from space
What is an Earth station in the amateur satellite service?
An amateur station within 50 km of the Earth's surface intended for communications with amateur stations by means of objects in space
An amateur station that is not able to communicate using amateur satellites
An amateur station that transmits telemetry consisting of measurement of upper atmosphere data from space
Any amateur station on the surface of the Earth
What class of licensee is authorized to be the control operator of a space station?
All except Technician Class
Only General, Advanced or Amateur Extra Class
All classesAny class with appropriate operator privileges
Only Amateur Extra Class
Which of the following special provisions must a space station incorporate in order to comply with is a requirement of a space station? requirements?
The space station must be capable of terminating transmissions by telecommand when directed by the FCC
The space station must cease all transmissions after 5 years
The space station must be capable of changing its orbit whenever such a change is ordered by NASA
All of these choices are correct
Which amateur service HF bands have frequencies authorized tofor space stations?
Only the 40 m, 20 m, 17 m, 15 m, 12 m and 10 m bands40m, 20m, 17m, 15m, 12m and 10m
Only 40m, 20m, 17m, 15m and 10m the 40 m, 20 m, 17 m, 15 m and 10 m bands
40m, 30m, 20m, 15m, 12m and 10m Only the 40 m, 30 m, 20 m, 15 m, 12 m and 10 m bands
All HF bands
Which VHF amateur service bands have frequencies available for space stations?
6 meters and 2 meters
6 meters, 2 meters, and 1.25 meters
2 meters and 1.25 meters
2 meters
- NEW -
Which UHF amateur service bands have frequencies available for a space station?
70 cm only
70 cm and 13 cm
70 cm and 33 cm
33 cm and 13 cm
Which amateur stations are eligible to be telecommand stations?
Any amateur station designated by NASA
Any amateur station so designated by the space station licensee, subject to the privileges of the class of operator license held by the control operator
Any amateur station so designated by the ITU
All of these choices are correct
Which amateur stations are eligible to operate as Earth stations?
Any amateur station whose licensee has filed a pre-space notification with the FCC's International Bureau
Only those of General, Advanced or Amateur Extra Class operators
Only those of Amateur Extra Class operators
Any amateur station, subject to the privileges of the class of operator license held by the control operator
Section E1E
Volunteer examiner program: definitions; qualifications; preparation and administration of exams; accreditation; question pools; documentation requirements
Removed questions: 1
New questions: 1
Updated questions: 0
Total questions: 14
REMOVED
What are the consequences of failing to appear for re-administration of an examination when so directed by the FCC?
The licensee's license will be cancelled
The person may be fined or imprisoned
The licensee is disqualified from any future examination for an amateur operator license grant
All these choices are correct
What is the minimum number of qualified VEs required to administer an Element 4 amateur operator license examination?
5
2
4
3
Where are the questions for all written USU.S. amateur license examinations listed?
In FCC Part 97
In a question pool maintained by the FCC
In a question pool maintained by all the VECs
In the appropriate FCC Report and Order
What is a Volunteer Examiner Coordinator?
A person who has volunteered to administer amateur operator license examinations
A person who has volunteered to prepare amateur operator license examinations
An organization that has entered into an agreement with the FCC to coordinate amateur operator license examinations
The person who has entered into an agreement with the FCC to be the VE session manager
Which of the following best describes the Volunteer Examiner accreditation process?
Each General, Advanced and Amateur Extra Class operator is automatically accredited as a VE when the license is granted
The amateur operator applying must pass a VE examination administered by the FCC Enforcement Bureau
The prospective VE obtains accreditation from the FCC
The procedure by which a VEC confirms that the VE applicant meets FCC requirements to serve as an examiner
What is the minimum passing score on amateur operator license examinations?
Minimum passing score of 70%
Minimum passing score of 74%
Minimum passing score of 80%
Minimum passing score of 77%
Who is responsible for the proper conduct and necessary supervision during an amateur operator license examination session?
The VEC coordinating the session
The FCC
Each administering VE
The VE session manager
What should a VE do if a candidate fails to comply with the examiner's instructions during an amateur operator license examination?
Warn the candidate that continued failure to comply will result in termination of the examination
Immediately terminate the candidate's examination
Allow the candidate to complete the examination, but invalidate the results
Immediately terminate everyoneseveryone's examination and close the session
To which of the following examinees may a VE not administer an examination?
Employees of the VE
Friends of the VE
Relatives of the VE as listed in the FCC rules
All of these choices are correct
What may be the penalty for a VE who fraudulently administers or certifies an examination?
Revocation of the VE's amateur station license grant and the suspension of the VE's amateur operator license grant
A fine of up to $1000 per occurrence
A sentence of up to one year in prison
All of these choices are correct
What must the administering VEs do after the administration of a successful examination for an amateur operator license?
They must collect and send the documents to the NCVEC for grading
They must collect and submit the documents to the coordinating VEC for grading
They must submit the application document to the coordinating VEC according to the coordinating VEC instructions
They must collect and send the documents to the FCC according to instructions
What must the VE team do if an examinee scores a passing grade on all examination elements needed for an upgrade or new license?
Photocopy all examination documents and forward them to the FCC for processing
Three VEs must certify that the examinee is qualified for the license grant and that they have complied with the administering VE requirements
Issue the examinee the new or upgrade license
All these choices are correct
What must the VE team do with the application form if the examinee does not pass the exam?
Return the application document to the examinee
Maintain the application form with the VEC's records
Send the application form to the FCC and inform the FCC of the grade
Destroy the application form
- NEW -
Which of these choices is an acceptable method for monitoring the applicants if a VEC opts to conduct an exam session remotely?
Record the exam session on video tape for later review by the VE team
Use a real-time video link and the Internet to connect the exam session to the observing VEs
The exam proctor observes the applicants and reports any violations
Have each applicant sign an affidavit stating that all session rules were followed
For which types of out-of-pocket expenses do the Part 97 rules state that VEs and VECs may be reimbursed?
Preparing, processing, administering and coordinating an examination for an amateur radio license
Teaching an amateur operator license examination preparation course
No expenses are authorized for reimbursement
Providing amateur operator license examination preparation training materials
Section E1F
Miscellaneous rules: external RF power amplifiers; national quiet zone; business communications; compensated communications; spread spectrum; auxiliary stations; reciprocal operating privileges; IARP and CEPT licenses; third party communications with foreign countries; special temporary authority
Removed questions: 0
New questions: 1
Updated questions: 1
Total questions: 12
On what frequencies are spread spectrum transmissions permitted?
Only on amateur frequencies above 50 MHz
Only on amateur frequencies above 222 MHz
Only on amateur frequencies above 420 MHz
Only on amateur frequencies above 144 MHz
- NEW -
What privileges are authorized in the U.S. to persons holding an amateur service license granted by the Government of Canada?
None, they must obtain a U.S. license
All privileges of the Extra Class license
The operating terms and conditions of the Canadian amateur service license, not to exceed U.S. Extra Class privileges
Full privileges, up to and including those of the Extra Class License, on the 80, 40, 20, 15, and 10 meter bands
Under what circumstances may a dealer sell an external RF power amplifier capable of operation below 144 MHz if it has not been granted FCC certification?
It was purchased in used condition from an amateur operator and is sold to another amateur operator for use at that operator's station
The equipment dealer assembled it from a kit
It was imported from a manufacturer in a country that does not require certification of RF power amplifiers
It was imported from a manufacturer in another country, and it was certificated by that country's government
Which of the following geographic descriptions approximately describes "Line A"?
A line roughly parallel to and south of the US-U.S.-Canadian border
A line roughly parallel to and west of the USU.S. Atlantic coastline
A line roughly parallel to and north of the US-U.S.-Mexican border and Gulf coastline
A line roughly parallel to and east of the USU.S. Pacific coastline
Amateur stations may not transmit in which of the following frequency segments if they are located in the contiguous 48 states and north of Line A?
440 - 450 MHz440 MHz - 450 MHz
53 - 54 MHz53 MHz - 54 MHz
222 - 223 MHz222 MHz - 223 MHz
420 - 430 MHz420 MHz - 430 MHz
was E1F14
Under what circumstances might the FCC issue a "Special Temporary Authority" (STA) to an amateur station?
To provide for experimental amateur communications
To allow regular operation on Land Mobile channels
To provide additional spectrum for personal use
To provide temporary operation while awaiting normal licensing
When may an amateur station send a message to a business?
When the total money involved does not exceed $25
When the control operator is employed by the FCC or another government agency
When transmitting international third-party communications
When neither the amateur nor his or her employer has a pecuniary interest in the communications
Which of the following types of amateur station communications are prohibited?
Communications transmitted for hire or material compensation, except as otherwise provided in the rules
Communications that have a political content, except as allowed by the Fairness Doctrine
Communications that have a religious content
Communications in a language other than English
Which of the following conditions apply when transmitting spread spectrum emission?
A station transmitting SS emission must not cause harmful interference to other stations employing other authorized emissions
The transmitting station must be in an area regulated by the FCC or in a country that permits SS emissions
The transmission must not be used to obscure the meaning of any communication
All of these choices are correct
What is the maximum permitted transmitter peak envelope power for an amateur station transmitting spread spectrum communications?
1 W
1.5 W
10 W
1.5 kW
Which of the following best describes one of the standards that must be met by an external RF power amplifier if it is to qualify for a grant of FCC certification?
It must produce full legal output when driven by not more than 5 watts of mean RF input power
It must be capable of external RF switching between its input and output networks
It must exhibit a gain of 0 dB or less over its full output range
It must satisfy the FCC's spurious emission standards when operated at the lesser of 1500 watts, or its full output power
Who may be the control operator of an auxiliary station?
Any licensed amateur operator
Only Technician, General, Advanced or Amateur Extra Class operators
Only General, Advanced or Amateur Extra Class operators
Only Amateur Extra Class operators
Subelement E2
OPERATING PROCEDURES
Removed questions: 3
New questions: 9
Updated questions: 8
Total questions: 73
Section E2A
Amateur radio in space: amateur satellites; orbital mechanics; frequencies and modes; satellite hardware; satellite operations; experimental telemetry applications
Removed questions: 0
New questions: 1
Updated questions: 0
Total questions: 14
What is the direction of an ascending pass for an amateur satellite?
From west to east
From east to west
From south to north
From north to south
What is the direction of a descending pass for an amateur satellite?
From north to south
From west to east
From east to west
From south to north
What is the orbital period of an Earth satellite?
The point of maximum height of a satellite's orbit
The point of minimum height of a satellite's orbit
The time it takes for a satellite to complete one revolution around the Earth
The time it takes for a satellite to travel from perigee to apogee
What is meant by the term mode as applied to an amateur radio satellite?
The type of signals that can be relayed through the satellite
The satellite's uplink and downlink frequency bands
The satellite's orientation with respect to the Earth
Whether the satellite is in a polar or equatorial orbit
What do the letters in a satellite's mode designator specify?
Power limits for uplink and downlink transmissions
The location of the ground control station
The polarization of uplink and downlink signals
The uplink and downlink frequency ranges
On what band would a satellite receive signals if it were operating in mode U/V?
435-438 MHz435 MHz - 438 MHz
144-146 MHz144 MHz - 146 MHz
50.0-50.2 MHz50.0 MHz - 50.2 MHz
29.5 to MHz - 29.7 MHz
Which of the following types of signals can be relayed through a linear transponder?
FM and CW
SSB and SSTV
PSK and Packet
All of these choices are correct
Why should effective radiated power to a satellite which uses a linear transponder be limited?
To prevent creating errors in the satellite telemetry
To avoid reducing the downlink power to all other users
To prevent the satellite from emitting out of -of-band signals
To avoid interfering with terrestrial QSOs
What do the terms L band and S band specify with regard to satellite communications?
The 23 centimeter and 13 centimeter bands
The 2 meter and 70 centimeter bands
FM and Digital Store-and-Forward systems
Which sideband to use
Why may the received signal from an amateur satellite exhibit a rapidly repeating fading effect?
Because the satellite is spinning
Because of ionospheric absorption
Because of the satellite's low orbital altitude
Because of the Doppler Effect
What type of antenna can be used to minimize the effects of spin modulation and Faraday rotation?
A linearly polarized antenna
A circularly polarized antenna
An isotropic antenna
A log-periodic dipole array
What is one way to predict the location of a satellite at a given time?
By means of the Doppler data for the specified satellite
By subtracting the mean anomaly from the orbital inclination
By adding the mean anomaly to the orbital inclination
By calculations using the Keplerian elements for the specified satellite
What type of satellite appears to stay in one position in the sky?
HEO
Geostationary
Geomagnetic
LEO
- NEW -
What technology is used to track, in real time, balloons carrying amateur radio transmitters?
Radar
Bandwidth compressed LORAN
APRS
Doppler shift of beacon signals
Section E2B
Television practices: fast scan television standards and techniques; slow scan television standards and techniques
Removed questions: 0
New questions: 0
Updated questions: 1
Total questions: 19
How many times per second is a new frame transmitted in a fast-scan (NTSC) television system?
30
60
90
120
How many horizontal lines make up a fast-scan (NTSC) television frame?
30
60
525
1080
How is an interlaced scanning pattern generated in a fast-scan (NTSC) television system?
By scanning two fields simultaneously
By scanning each field from bottom to top
By scanning lines from left to right in one field and right to left in the next
By scanning odd numbered lines in one field and even numbered oneslines in the next
What is blanking in a video signal?
Synchronization of the horizontal and vertical sync pulses
Turning off the scanning beam while it is traveling from right to left or from bottom to top
Turning off the scanning beam at the conclusion of a transmission
Transmitting a black and white test pattern
Which of the following is an advantage of using vestigial sideband for standard fast- scan TV transmissions?
The vestigial sideband carries the audio information
The vestigial sideband contains chroma information
Vestigial sideband reduces bandwidth while allowing for simple video detector circuitry
Vestigial sideband provides high frequency emphasis to sharpen the picture
What is vestigial sideband modulation?
Amplitude modulation in which one complete sideband and a portion of the other are transmitted
A type of modulation in which one sideband is inverted
Narrow-band FM transmissionmodulation achieved by filtering one sideband from the audio before frequency modulating the carrier
Spread spectrum modulation achieved by applying FM modulation following single sideband amplitude modulation
What is the name of the signal component that carries color information in NTSC video?
Luminance
Chroma
Hue
Spectral Intensity
Which of the following is a common method of transmitting accompanying audio with amateur fast-scan television?
Frequency-modulated sub-carrier
A separate VHF or UHF audio link
Frequency modulation of the video carrier
All of these choices are correct
What hardware, other than a receiver with SSB capability and a suitable computer, is needed to decode SSTV using Digital Radio Mondiale (DRM)?
A special IF converter
A special front end limiter
A special notch filter to remove synchronization pulses
No other hardware is needed
Which of the following is an acceptable bandwidth for Digital Radio Mondiale (DRM) based voice or SSTV digital transmissions made on the HF amateur bands?
3 KHz
10 KHz
15 KHz
20 KHz
What is the function of the Vertical Interval Signaling (VIS) code transmittedsent as part of an SSTV transmission?
To lock the color burst oscillator in color SSTV images
To identify the SSTV mode being used
To provide vertical synchronization
To identify the call sign of the station transmitting
How are analog SSTV images typically transmitted on the HF bands?
Video is converted to equivalent Baudot representation
Video is converted to equivalent ASCII representation
Varying tone frequencies representing the video are transmitted using PSK
Varying tone frequencies representing the video are transmitted using single sideband
How many lines are commonly used in each frame onof an amateur slow-scan color television picture?
30 to 6030 or 60
60 or 100
128 or 256
180 or 360
What aspect of an amateur slow-scan television signal encodes the brightness of the picture?
Tone frequency
Tone amplitude
Sync amplitude
Sync frequency
What signals SSTV receiving equipment to begin a new picture line?
Specific tone frequencies
Elapsed time
Specific tone amplitudes
A two-tone signal
Which of the following is theis a video standard used by North American Fast Scan ATV stations?
PAL
DRM
Scottie
NTSC
What is the approximate bandwidth of a slow-scan TV signal?
600 Hz
3 kHz
2 MHz
6 MHz
On which of the following frequencies is one likely to find FM ATV transmissions?
14.230 MHz
29.6 MHz
52.525 MHz
1255 MHz
What special operating frequency restrictions are imposed on slow scan TV transmissions?
None; they are allowed on all amateur frequencies
They are restricted to 7.245 MHz, 14.245 MHz, 21.345, MHz, and 28.945 MHz
They are restricted to phone band segments and their bandwidth can be no greater than that of a voice signal of the same modulation type
They are not permitted above 54 MHz
Section E2C
Operating methods: contest and DX operating; remote operation techniques; Cabrillo format; QSLing; RF network connected systemsspread-spectrum transmissions; selecting an operating frequency
Removed questions: 1
New questions: 4
Updated questions: 1
Total questions: 13
REMOVED
On which of the following frequencies is an amateur radio contest contact generally discouraged?
3.525 MHz
14.020 MHz
28.330 MHz
146.52 MHz
Which of the following is true about contest operating?
Operators are permitted to make contacts even if they do not submit a log
Interference to other amateurs is unavoidable and therefore acceptable
It is mandatory to transmit the call sign of the station being worked as part of every transmission to that station
Every contest requires a signal report in the exchange
Which of the following best describes the term "self-spotting" in regards to HF contest operating?
The generally prohibited practice of posting one's own call sign and frequency on a call sign spotting network
The acceptable practice of manually posting the call signs of stations on a call sign spotting network
A manual technique for rapidly zero beating or tuning to a station's frequency before calling that station
An automatic method for rapidly zero beating or tuning to a station's frequency before calling that station
From which of the following bands is amateur radio contesting generally excluded?
30 meters30 m
6 meters6 m
2 meters2 m
33 cm
- NEW -
What type of transmission is most often used for a ham radio mesh network?
Spread spectrum in the 2.4 GHz band
Multiple Frequency Shift Keying in the 10 GHz band
Store and forward on the 440 MHz band
Frequency division multiplex in the 24 GHz band
What is the function of a DX QSL Manager?
To allocate frequencies for DXpeditions
To handle the receiving and sending of confirmation cards for a DX station
To run a net to allow many stations to contact a rare DX station
To relay calls to and from a DX station
During a VHF/UHF contest, in which band segment would you expect to find the highest level of activity?
At the top of each band, usually in a segment reserved for contests
In the middle of each band, usually on the national calling frequency
In the weak signal segment of the band, with most of the activity near the calling frequency
In the middle of the band, usually 25 kHz above the national calling frequency
What is the Cabrillo format?
A standard for submission of electronic contest logs
A method of exchanging information during a contest QSO
The most common set of contest rules
The rules of order for meetings between contest sponsors
- NEW -
Which of the following contacts may be confirmed through the U.S. QSL bureau system?
Special event contacts between stations in the U.S.
Contacts between a U.S. station and a non-U.S. station
Repeater contacts between U.S. club members
Contacts using tactical call signs
- NEW -
What type of equipment is commonly used to implement a ham radio mesh network?
A 2 meter VHF transceiver with a 1200 baud modem
An optical cable connection between the USB ports of 2 separate computers
A standard wireless router running custom software
A 440 MHz transceiver with a 9600 baud modem
Why might a DX station state that they are listening on another frequency?
Because the DX station may be transmitting on a frequency that is prohibited to some responding stations
To separate the calling stations from the DX station
To improve operating efficiency by reducing interferenceTo reduce interference, thereby improving operating efficiency
All of these choices are correct
How should you generally identify your station when attempting to contact a DX station working a pileupduring a contest or in a pileup?contest?
Send your full call sign once or twice
Send only the last two letters of your call sign until you make contact
Send your full call sign and grid square
Send the call sign of the DX station three times, the words "this is", then your call sign three times
What might help to restore contact when DX signals become too weak to copy across an entire HF band a few hours after sunset?
Switch to a higher frequency HF band
Switch to a lower frequency HF band
Wait 90 minutes or so for the signal degradation to pass
Wait 24 hours before attempting another communication on the band
- NEW -
What indicator is required to be used by U.S.-licensed operators when operating a station via remote control where the transmitter is located in the U.S.?
/ followed by the USPS two letter abbreviation for the state in which the remote station is located
/R# where # is the district of the remote station
The ARRL section of the remote station
No additional indicator is required
Section E2D
Operating methods: VHF and UHF digital modes and procedures; APRS; EME procedures, meteor scatter procedures
Removed questions: 2
New questions: 1
Updated questions: 3
Total questions: 14
REMOVED
What is the definition of baud?
The number of data symbols transmitted per second
The number of characters transmitted per second
The number of characters transmitted per minute
The number of words transmitted per minute
REMOVED
Which of the following is a commonly used 2-meter APRS frequency?
144.39 MHz
144.20 MHz
145.02 MHz
146.52 MHz
Which of the following digital modes is especially designed for use for meteor scatter signals?
WSPR
FSK441
Hellschreiber
APRS
was E3A10
Which of the following is a good technique for making meteor- scatter contacts?
15 second timed transmission sequences with stations alternating based on location
Use of high speed CW or digital modes
Short transmission with rapidly repeated call signs and signal reports
All of these choices are correct
Which of the following digital modes is especially useful for EME communications?
FSK441
PACTOR III
Olivia
JT65
What is the purpose of digital store-and-forward functions on an Amateur Radio satellite?
To upload operational software for the transponder
To delay download of telemetry between satellites
To store digital messages in the satellite for later download by other stations
To relay messages between satellites
Which of the following techniques is normally used by low Earth orbiting digital satellites to relay messages around the world?
Digipeating
Store-and-forward
Multi-satellite relaying
Node hopping
was E3A05
Which of the following describes a method of establishing EME contacts?
Time synchronous transmissions with alternately from each station alternating
Storing and forwarding digital messages
Judging optimum transmission times by monitoring beacons reflected from the Moon
High speed CW identification to avoid fading
Which of the following What digital protocolsprotocol is used by APRS?
PACTOR
802.11
AX.25
AMTOR
Which of the following types What type of packet framesframe is used to transmit APRS beacon data?
Unnumbered Information
Disconnect
Acknowledgement
Connect
Under clear communications conditions, which Which of these digital communications modes has the fastest data throughput under clear communication conditions??
AMTOR
170-170 Hz shift, 45 baud RTTY
PSK31
300-300 baud packet
How can an APRS station be used to help support a public service communications activity?
An APRS station with an emergency medical technician can automatically transmit medical data to the nearest hospital
APRS stations with General Personnel Scanners can automatically relay the participant numbers and time as they pass the check points
An APRS station with a GPS unit can automatically transmit information to show a mobile station's position during the event
All of these choices are correct
Which of the following data are used by the APRS network to communicate your location?
Polar coordinates
Time and frequency
Radio direction finding spectrum analysisLOPs
Latitude and longitude
How does JT65 improve EME communications?
It can decode signals many dB below the noise floor using FEC
It controls the receiver to track Doppler shift
It supplies signals to guide the antenna to track the Moon
All of these choices are correct
- NEW -
What type of modulation is used for JT65 contacts?
Multi-tone AFSK
PSK
RTTY
IEEE 802.11
was E8C13
What is one advantage of using JT-65JT65 coding?
Uses only a 65 Hz bandwidth
The ability to decode signals which have a very low signal to noise ratio
Easily copied by ear if necessary
Permits fast-scan TV transmissions over narrow bandwidth
Section E2E
Operating methods: operating HF digital modes; error correction
Removed questions: 0
New questions: 3
Updated questions: 3
Total questions: 13
Which type of modulation is common for data emissions below 30 MHz?
DTMF tones modulating an FM signal
FSK
Pulse modulation
Spread spectrum
What do the letters FEC mean as they relate to digital operation?
Forward Error Correction
First Error Correction
Fatal Error Correction
Final Error Correction
- NEW -
How is the timing of JT65 contacts organized?
By exchanging ACK/NAK packets
Stations take turns on alternate days
Alternating transmissions at 1 minute intervals
It depends on the lunar phase
What is indicated when one of the ellipses in an FSK crossed-ellipse display suddenly disappears?
Selective fading has occurred
One of the signal filters hasis saturated
The receiver has drifted 5 kHz from the desired receive frequency
The mark and space signal have been inverted
was E2E12
Which type of digital communicationmode does not support keyboard-to-keyboard operation?
Winlink
RTTY
PSK31
MFSK
What is the most common data rate used for HF packet? communications?
48 baud
110 baud
300 baud
1200 baud
What is the typical bandwidth of a properly modulated MFSK16 signal?
31 Hz
316 Hz
550 Hz
2.16 kHz
Which of the following HF digital modes can be used to transfer binary files?
Hellschreiber
PACTOR
RTTY
AMTOR
Which of the following HF digital modes uses variable-length coding for bandwidth efficiency?
RTTY
PACTOR
MT63
PSK31
Which of these digital communications modes has the narrowest bandwidth?
MFSK16
170-170 Hz shift, 45 baud RTTY
PSK31
300-baud packet
What is the difference between direct FSK and audio FSK?
Direct FSK applies the data signal to the transmitter VFO
Audio FSK has a superior frequency response
Direct FSK uses a DC-coupled data connection
Audio FSK can be performed anywhere in the transmit chain
- NEW -
Which type of control is used by stations using the Automatic Link Enable (ALE) protocol?
Local
Remote
Automatic
ALE can use any type of control
- NEW -
Which of the following is a possible reason that attempts to initiate contact with a digital station on a clear frequency are unsuccessful?
Your transmit frequency is incorrect
The protocol version you are using is not the supported by the digital station
Another station you are unable to hear is using the frequency
All of these choices are correct
Subelement E3
RADIO WAVE PROPAGATION
Removed questions: 11
New questions: 23
Updated questions: 3
Total questions: 46
Section E3A
Propagation and technique: Electromagnetic waves; Earth-Moon-Earth communications (EME), ; meteor scatter; microwave tropospheric and scatter propagation; aurora propagation
Removed questions: 3
New questions: 6
Updated questions: 2
Total questions: 17
REMOVED
What type of receiving system is desirable for EME communications?
Equipment with very wide bandwidth
Equipment with very low dynamic range
Equipment with very low gain
Equipment with very low noise figures
REMOVED
What frequency range would you normally tune to find EME signals in the 2 meter band?
144.000 - 144.001 MHz
144.000 - 144.100 MHz
144.100 - 144.300 MHz
145.000 - 145.100 MHz
REMOVED
What frequency range would you normally tune to find EME signals in the 70 cm band?
430.000 - 430.150 MHz
430.100 - 431.100 MHz
431.100 - 431.200 MHz
432.000 - 432.100 MHz
What is the approximate maximum separation measured along the surface of the Earth between two stations communicating by Moon bounce?
500 miles, if the Moon is at perigee
2000 miles, if the Moon is at apogee
5000 miles, if the Moon is at perigee
12,000 miles, if the Moon is visible by both stationsas long as both can "see" the Moon
What characterizes libration fading of an Earth-Moon-EarthEME signal?
A slow change in the pitch of the CW signal
A fluttery irregular fading
A gradual loss of signal as the Sun rises
The returning echo is several Hertz lower in frequency than the transmitted signal
When scheduling EME contacts, which of these conditions will generally result in the least path loss?
When the Moon is at perigee
When the Moon is full
When the Moon is at apogee
When the MUF is above 30 MHz
- NEW -
What do Hepburn maps predict?
Sporadic E propagation
Locations of auroral reflecting zones
Likelihood of rain-scatter along cold or warm fronts
Probability of tropospheric propagation
- NEW -
Tropospheric propagation of microwave signals often occurs along what weather related structure?
Gray-line
Lightning discharges
Warm and cold fronts
Sprites and jets
- NEW -
Which of the following is required for microwave propagation via rain scatter?
Rain droplets must be electrically charged
Rain droplets must be within the E layer
The rain must be within radio range of both stations
All of these choices are correct
- NEW -
Atmospheric ducts capable of propagating microwave signals often form over what geographic feature?
Mountain ranges
Forests
Bodies of water
Urban areas
When a meteor strikes the Earth's atmosphere, a cylindrical region of free electrons is formed at what layer of the ionosphere?
The E layer
The F1 layer
The F2 layer
The D layer
Which of the following frequency ranges is wellrange is most suited for meteor- scatter communications?
1.8 - 1.9 MHz1.8 MHz - 1.9 MHz
10 - 14 MHz10 MHz - 14 MHz
28 - 148 MHz28 MHz - 148 MHz
220 - 450 MHz220 MHz - 450 MHz
- NEW -
Which type of atmospheric structure can create a path for microwave propagation?
The jet stream
Temperature inversion
Wind shear
Dust devil
- NEW -
What is a typical range for tropospheric propagation of microwave signals?
10 miles to 50 miles
100 miles to 300 miles
1200 miles
2500 miles
was E3C02
What is the cause of Auroraauroral activity?
The interaction in the F2 layer between the solar wind and the Van Allen belt
A low sunspot level combined with tropospheric ducting
The interaction in the E layer of charged particles from the Sun with the Earth's magnetic field and the ionosphere
Meteor showers concentrated in the extreme northern and southern latitudes
was E3C04
Which emission mode is best for Auroraaurora propagation?
CW
SSB
FM
RTTY
was E3C11
From the contiguous 48 states, in which approximate direction should an antenna be pointed to take maximum advantage of aurora propagation?
South
North
East
West
was E8D07
What is an electromagnetic wave?
Alternating currents A wave of alternating current, in the core of an electromagnet
A wave consisting of two electric fields at parallel right angles to each other
A wave consisting of an electric field and a magnetic field oscillating at right angles to each other
A wave consisting of two magnetic fields at right angles to each other
was E8D08
Which of the following best describes electromagnetic waves traveling in free space?
Electric and magnetic fields become aligned as they travel
The energy propagates through a medium with a high refractive index
The waves are reflected by the ionosphere and return to their source
Changing electric and magnetic fields propagate the energy
was E8D09
What is meant by circularly polarized electromagnetic waves?
Waves with an electric field bent into a circular shape
Waves with a rotating electric field
Waves that circle the Earth
Waves produced by a loop antenna
Section E3B
Propagation and technique: trans-equatorial, Transequatorial propagation; long path,; gray-line; multi-path; ordinary and extraordinary waves; chordal hop, sporadic E mechanisms propagation
Removed questions: 3
New questions: 6
Updated questions: 0
Total questions: 14
REMOVED
What type of propagation is probably occurring if an HF beam antenna must be pointed in a direction 180 degrees away from a station to receive the strongest signals?
Long-path
Sporadic-E
Transequatorial
Auroral
REMOVED
At what time of day is gray-line propagation most likely to occur?
At sunrise and sunset
When the Sun is directly above the location of the transmitting station
When the Sun is directly overhead at the middle of the communications path between the two stations
When the Sun is directly above the location of the receiving station
REMOVED
Which of the following describes gray-line propagation?
Backscatter contacts on the 10 meter band
Over the horizon propagation on the 6 and 2 meter bands
Long distance communications at twilight on frequencies less than 15 MHz
Tropospheric propagation on the 2 meter and 70 centimeter bands
What is transequatorial propagation?
Propagation between two mid-latitude points at approximately the same distance north and south of the magnetic equator
Propagation between any two points located on the magnetic equator
Propagation between two continents by way of ducts along the magnetic equator
Propagation between two stations at the same latitude
What is the approximate maximum range for signals using transequatorial propagation?
1000 miles
2500 miles
5000 miles
7500 miles
What is the best time of day for transequatorial propagation?
Morning
Noon
Afternoon or early evening
Late at night
- NEW -
What is meant by the terms extraordinary and ordinary waves?
Extraordinary waves describe rare long skip propagation compared to ordinary waves which travel shorter distances
Independent waves created in the ionosphere that are elliptically polarized
Long path and short path waves
Refracted rays and reflected waves
Which amateur bands typically support long-path propagation?
160 160 meters to 40 meters
30 30 meters to 10 meters
160 160 meters to 10 meters
6 meters to 2 meters
Which of the following amateur bands most frequently provides long-path propagation?
80 meters
20 meters
10 meters
6 meters
Which of the following could account for hearing an echo on the received signal of a distant station?
High D layer absorption
Meteor scatter
Transmit frequency is higher than the MUF
Receipt of a signal by more than one path
What type of HF propagation is probably occurring if radio signals travel along the terminator between daylight and darkness?
Transequatorial
Sporadic-E
Long-path
Gray-line
- NEW -
At what time of year is Sporadic E propagation most likely to occur?
Around the solstices, especially the summer solstice
Around the solstices, especially the winter solstice
Around the equinoxes, especially the spring equinox
Around the equinoxes, especially the fall equinox
What is the cause of gray-line propagation?
At midday, the Sun being directly overhead superheats super heats the ionosphere causing increased refraction of radio waves
At twilight and sunrise, D-layer absorption drops is low while E-layer and F-layer propagation remains highremain strong
In darkness, solar absorption drops greatly while atmospheric ionization remains steady
At mid-afternoon, the Sun heats the ionosphere decreasing radio wave refraction and the MUF
- NEW -
At what time of day is Sporadic-E propagation most likely to occur?
Around sunset
Around sunrise
Early evening
Any time
- NEW -
What is the primary characteristic of chordal hop propagation?
Propagation away from the great circle bearing between stations
Successive ionospheric reflections without an intermediate reflection from the ground
Propagation across the geomagnetic equator
Signals reflected back toward the transmitting station
- NEW -
Why is chordal hop propagation desirable?
The signal experiences less loss along the path compared to normal skip propagation
The MUF for chordal hop propagation is much lower than for normal skip propagation
Atmospheric noise is lower in the direction of chordal hop propagation
Signals travel faster along ionospheric chords
- NEW -
What happens to linearly polarized radio waves that split into ordinary and extraordinary waves in the ionosphere?
They are bent toward the magnetic poles
Their polarization is randomly modified
They become elliptically polarized
They become phase-locked
Section E3C
Propagation and technique: Aurora propagation selective fading; radioRadio-path horizon; less common propagation modes; propagation prediction techniques and modeling; space weather parameters and amateur radiotake-off angle over flat or sloping terrain; effects of ground on propagation; less common propagation modes
Removed questions: 5
New questions: 11
Updated questions: 1
Total questions: 15
REMOVED
Which of the following effects does Aurora activity have on radio communications?
SSB signals are raspy
Signals propagating through the Aurora are fluttery
CW signals appear to be modulated by white noise
All of these choices are correct
REMOVED
Where in the ionosphere does Aurora activity occur?
In the F1-region
In the F2-region
In the D-region
In the E-region
REMOVED
Which of the following describes selective fading?
Variability of signal strength with beam heading
Partial cancellation of some frequencies within the received pass band
Sideband inversion within the ionosphere
Degradation of signal strength due to backscatter
REMOVED
What is the name of the high-angle wave in HF propagation that travels for some distance within the F2 region?
Oblique-angle ray
Pedersen ray
Ordinary ray
Heaviside ray
REMOVED
Which of the following is usually responsible for causing VHF signals to propagate for hundreds of miles?
D-region absorption
Faraday rotation
Tropospheric ducting
Ground wave
- NEW -
What does the term ray tracing describe in regard to radio communications?
The process in which an electronic display presents a pattern
Modeling a radio wave's path through the ionosphere
Determining the radiation pattern from an array of antennas
Evaluating high voltage sources for X-Rays
- NEW -
What is indicated by a rising A or K index?
Increasing disruption of the geomagnetic field
Decreasing disruption of the geomagnetic field
Higher levels of solar UV radiation
An increase in the critical frequency
- NEW -
Which of the following signal paths is most likely to experience high levels of absorption when the A index or K index is elevated?
Transequatorial propagation
Polar paths
Sporadic-E
NVIS
- NEW -
What does the value of Bz (B sub Z) represent?
Geomagnetic field stability
Critical frequency for vertical transmissions
Direction and strength of the interplanetary magnetic field
Duration of long-delayed echoes
- NEW -
What orientation of Bz (B sub z) increases the likelihood that incoming particles from the Sun will cause disturbed conditions?
Southward
Northward
Eastward
Westward
By how much does the VHF/UHF radio-path horizon distance exceed the geometric horizon?
By approximately 15% percent of the distance
By approximately twice the distance
By approximately one-half 50 percent of the distance
By approximately four times the distance
- NEW -
Which of the following descriptors indicates the greatest solar flare intensity?
Class A
Class B
Class M
Class X
- NEW -
What does the space weather term G5 mean?
An extreme geomagnetic storm
Very low solar activity
Moderate solar wind
Waning sunspot numbers
- NEW -
How does the intensity of an X3 flare compare to that of an X2 flare?
10 percent greater
50 percent greater
Twice as great
Four times as great
- NEW -
What does the 304A solar parameter measure?
The ratio of X-Ray flux to radio flux, correlated to sunspot number
UV emissions at 304 angstroms, correlated to solar flux index
The solar wind velocity at 304 degrees from the solar equator, correlated to solar activity
The solar emission at 304 GHz, correlated to X-Ray flare levels
- NEW -
What does VOACAP software model?
AC voltage and impedance
VHF radio propagation
HF propagation
AC current and impedance
How does the maximum distance of ground-wave propagation change when the signal frequency is increased?
It stays the same
It increases
It decreases
It peaks at roughly 14 MHz
What type of polarization is best for ground-wave propagation?
Vertical
Horizontal
Circular
Elliptical
Why does the radio-path horizon distance exceed the geometric horizon?
E-region skip
D-region skip
Downward bending due to aurora refraction
Downward bending due to density variations in the atmosphere
- NEW -
What might a sudden rise in radio background noise indicate?
A meteor ping
A solar flare has occurred
Increased transequatorial propagation likely
Long-path propagation is occurring
Subelement E4
AMATEUR PRACTICES
Removed questions: 9
New questions: 16
Updated questions: 7
Total questions: 79
Section E4A
Test equipment: analog and digital instruments; spectrum and network analyzers, antenna analyzers; oscilloscopes; testing transistors; RF RF measurements; computer aided measurements
Removed questions: 7
New questions: 7
Updated questions: 2
Total questions: 15
REMOVED
How does a spectrum analyzer differ from an oscilloscope?
A spectrum analyzer measures ionospheric reflection; an oscilloscope displays electrical signals
A spectrum analyzer displays the peak amplitude of signals; an oscilloscope displays the average amplitude of signals
A spectrum analyzer displays signals in the frequency domain; an oscilloscope displays signals in the time domain
A spectrum analyzer displays radio frequencies; an oscilloscope displays audio frequencies
REMOVED
Which of the following parameters would a spectrum analyzer display on the horizontal axis?
SWR
Q
Time
Frequency
REMOVED
Which of the following parameters would a spectrum analyzer display on the vertical axis?
Amplitude
Duration
SWR
Q
REMOVED
Which of the following test instruments is used to display spurious signals from a radio transmitter?
A spectrum analyzer
A wattmeter
A logic analyzer
A time-domain reflectometer
REMOVED
Which of the following could be determined with a spectrum analyzer?
The degree of isolation between the input and output ports of a 2 meter duplexer
Whether a crystal is operating on its fundamental or overtone frequency
The spectral output of a transmitter
All of these choices are correct
REMOVED
Which of the following describes a good method for measuring the intermodulation distortion of your own PSK signal?
Transmit into a dummy load, receive the signal on a second receiver, and feed the audio into the sound card of a computer running an appropriate PSK program
Multiply the ALC level on the transmitter during a normal transmission by the average power output
Use an RF voltmeter coupled to the transmitter output using appropriate isolation to prevent damage to the meter
All of these choices are correct
REMOVED
Which of these instruments could be used for detailed analysis of digital signals?
Dip meter
Oscilloscope
Ohmmeter
Q meter
- NEW -
Which of the following parameter determines the bandwidth of a digital or computer-based oscilloscope?
Input capacitance
Input impedance
Sampling rate
Sample resolution
- NEW -
Which of the following parameters would a spectrum analyzer display on the vertical and horizontal axes?
RF amplitude and time
RF amplitude and frequency
SWR and frequency
SWR and time
was E4A05
Which of the following test instrumentsinstrument is used to display spurious signals and/or intermodulation distortion products in an SSB transmitter?transmission?
A wattmeter
A spectrum analyzer
A logic analyzer
A time-domain reflectometer
- NEW -
What determines the upper frequency limit for a computer soundcard-based oscilloscope program?
Analog-to-digital conversion speed of the soundcard
Amount of memory on the soundcard
Q of the interface of the interface circuit
All of these choices are correct
- NEW -
What might be an advantage of a digital vs an analog oscilloscope?
Automatic amplitude and frequency numerical readout
Storage of traces for future reference
Manipulation of time base after trace capture
All of these choices are correct
- NEW -
What is the effect of aliasing in a digital or computer-based oscilloscope?
False signals are displayed
All signals will have a DC offset
Calibration of the vertical scale is no longer valid
False triggering occurs
Which of the following is an advantage of using an antenna analyzer compared to an SWR bridge to measure antenna SWR?
Antenna analyzers automatically tune your antenna for resonance
Antenna analyzers do not need an external RF source
Antenna analyzers display a time-varying representation of the modulation envelope
All of these choices are correct
Which of the following instrumentsinstrument would be best for measuring the SWR of a beam antenna?
A spectrum analyzer
A Q meter
An ohmmeter
An antenna analyzer
- NEW -
When using a computer's soundcard input to digitize signals, what is the highest frequency signal that can be digitized without aliasing?
The same as the sample rate
One-half the sample rate
One-tenth the sample rate
It depends on how the data is stored internally
- NEW -
Which of the following displays multiple digital signal states simultaneously?
Network analyzer
Bit error rate tester
Modulation monitor
Logic analyzer
was E4B07
Which of the following is good practice when using an oscilloscope probe?
Keep the signal ground connection of the probe as short as possible
Never use a high impedance probe to measure a low impedance circuit
Never use a DC-coupled probe to measure an AC circuit
All of these choices are correct
Which of the following procedures is an important precaution to follow when connecting a spectrum analyzer to a transmitter output?
Use high quality double shielded coaxial cables to reduce signal losses
Attenuate the transmitter output going to the spectrum analyzer
Match the antenna to the load
All of these choices are correct
was E4B13
How is the compensation of an oscilloscope probe typically adjusted?
A square wave is displayed and the probe is adjusted until the horizontal portions of the displayed wave are as nearly flat as possible
A high frequency sine wave is displayed and the probe is adjusted for maximum amplitude
A frequency standard is displayed and the probe is adjusted until the deflection time is accurate
A DC voltage standard is displayed and the probe is adjusted until the displayed voltage is accurate
was E7F01
What is the purpose of athe prescaler function on a frequency counter?circuit?
It amplifies low level signals for more accurate countingIt converts the output of a JK flip flop to that of an RS flip-flop
It multiplies a higher frequency signal so a low-frequency counter can display the operating frequency
It prevents oscillation in a low-frequency counter circuit
It divides a higher frequency signal so a low-frequency counter can display the input frequency
was E7F11
What is an advantage of a period-measuring frequency counter over a direct-count type?
It can run on battery power for remote measurements
It does not require an expensive high-precision time base
It provides improved resolution of low-frequency signals within a comparable time period
It can directly measure the modulation index of an FM transmitter
Section E4B
Measurement techniques: Instrumenttechnique and limitations: instrument accuracy and performance limitations; probes; techniques to minimize errors; measurement of Q"Q"; instrument calibration; S parameters; vector network analyzers
Removed questions: 1
New questions: 4
Updated questions: 0
Total questions: 17
REMOVED
If a frequency counter with a specified accuracy of +/- 10 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading?
146.52 Hz
10 Hz
146.52 kHz
1465.20 Hz
Which of the following factors most affects the accuracy of a frequency counter?
Input attenuator accuracy
Time base accuracy
Decade divider accuracy
Temperature coefficient of the logic
What is an advantage of using a bridge circuit to measure impedance?
It provides an excellent match under all conditions
It is relatively immune to drift in the signal generator source
The measurement is based on It is very precise in obtaining a signal null, which can be done very precisely
It can display results directly in Smith chart format
If a frequency counter with a specified accuracy of +/- 1.0 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading?
165.2 Hz
14.652 kHz
146.52 Hz
1.4652 MHz
If a frequency counter with a specified accuracy of +/- 0.1 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading?
14.652 Hz
0.1 MHz
1.4652 Hz
1.4652 kHz
was E4B03
If a frequency counter with a specified accuracy of +/- 1.010 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading?
165.2 Hz146.52 Hz
14.652 kHz10 Hz
146.52 Hz146.52 kHz
1.4652 MHz1465.20 Hz
How much power is being absorbed by the load when a directional power meter connected between a transmitter and a terminating load reads 100 watts forward power and 25 watts reflected power?
100 watts
125 watts
25 watts
75 watts
- NEW -
What do the subscripts of S parameters represent?
The port or ports at which measurements are made
The relative time between measurements
Relative quality of the data
Frequency order of the measurements
Which of the following is a characteristic of a good DC voltmeter?
High reluctance input
Low reluctance input
High impedance input
Low impedance input
What is indicated if the current reading on an RF ammeter placed in series with the antenna feed line of a transmitter increases as the transmitter is tuned to resonance?
There is possibly a short to ground in the feed line
The transmitter is not properly neutralized
There is an impedance mismatch between the antenna and feed line
There is more power going into the antenna
Which of the following describes a method to measure intermodulation distortion in an SSB transmitter?
Modulate the transmitter with two non-harmonically related radio frequencies and observe the RF output with a spectrum analyzer
Modulate the transmitter with two non-harmonically related audio frequencies and observe the RF output with a spectrum analyzer
Modulate the transmitter with two harmonically related audio frequencies and observe the RF output with a peak reading wattmeter
Modulate the transmitter with two harmonically related audio frequencies and observe the RF output with a logic analyzer
How should a portable an antenna analyzer be connected when measuring antenna resonance and feed point impedance?
Loosely couple the analyzer near the antenna base
Connect the analyzer via a high-impedance transformer to the antenna
Connect Loosely couple the antenna and a dummy load to the analyzer
Connect the antenna feed line directly to the analyzer's connector
What is the significance of voltmeter sensitivity expressed in ohms per volt?
The full scale reading of the voltmeter multiplied by its ohms per/volt rating will provideindicate the input impedance of the voltmeter
When used as a galvanometer, the reading in volts multiplied by the ohms/volt rating will determine the power drawn by the device under test
When used as an ohmmeter, the reading in ohms divided by the ohms/volt rating will determine the voltage applied to the circuit
When used as an ammeter, the full scale reading in amps divided by ohms/volt rating will determine the size of shunt needed
- NEW -
Which S parameter is equivalent to forward gain?
S11
S12
S21
S22
What happens if a dip meter is too tightly coupled to a tuned circuit being checked?
Harmonics are generated
A less accurate reading results
Cross modulation occurs
Intermodulation distortion occurs
Which of the following can be used as a relative measurement of the Q for a series-tuned circuit?
The inductance to capacitance ratio
The frequency shift
The bandwidth of the circuit's frequency response
The resonant frequency of the circuit
- NEW -
Which S parameter represents return loss or SWR?
S11
S12
S21
S22
- NEW -
What three test loads are used to calibrate a standard RF vector network analyzer?
50 ohms, 75 ohms, and 90 ohms
Short circuit, open circuit, and 50 ohms
Short circuit, open circuit, and resonant circuit
50 ohms through 1/8 wavelength, 1/4 wavelength, and 1/2 wavelength of coaxial cable
How might lowering the noise figure affect receiver performance?
It would reduce the signal to noise ratio
It would improve weak signal sensitivity
It would reduce bandwidth
It would increase bandwidth
What is an effect of excessive phase noise in the local oscillator section of a receiver?
It limits the receiver's ability to receive strong signals
It reduces receiver sensitivity
It decreases receiver third-order intermodulation distortion dynamic range
It can cause strong signals on nearby frequencies to interfere with reception of weak signals
Which of the following portions of a receiver can be effective in eliminating image signal interference?
A front-end filter or pre-selector
A narrow IF filter
A notch filter
A properly adjusted product detector
What is the term for the blocking of one FM phone signal by another, stronger FM phone signal?
Desensitization
Cross-modulation interference
Capture effect
Frequency discrimination
WhatHow is the definition of the noise figure of a receiver defined??
The ratio of atmospheric noise to phase noise
The The ratio of the noise bandwidth in Hertz compared to the theoretical bandwidth of a resistive network
The ratio of thermal noise to atmospheric noise
The ratio in dB of the noise generated by the receiver compared to the theoretical minimum noise
What does a value of -174 dBm/Hz represent with regard to the noise floor of a receiver?
The minimum detectable signal as a function of receive frequency
The theoretical noise at the input of a perfect receiver at room temperature
The noise figure of a 1 Hz bandwidth receiver
The galactic noise contribution to minimum detectable signal
A CW receiver with the AGC off has an equivalent input noise power density of -174 dBm/Hz. What would be the level of an unmodulated carrier input to this receiver that would yield an audio output SNR of 0 dB in a 400 Hz noise bandwidth?
174 dBm-174 dBm
-164 dBm
-155 dBm
-148 dBm
What does the MDS of a receiver represent?
The meter display sensitivity
The minimum discernible signal
The multiplex distortion stability
The maximum detectable spectrum
- NEW -
An SDR receiver is overloaded when input signals exceed what level?
One-half the maximum sample rate
One-half the maximum sampling buffer size
The maximum count value of the analog-to-digital converter
The reference voltage of the analog-to-digital converter
Which of the following choices is a good reason for selecting a high frequency for the design of the IF in a conventional HF or VHF communications receiver?
Fewer components in the receiver
Reduced drift
Easier for front-end circuitry to eliminate image responses
Improved receiver noise figure
Which of the following is a desirable amount of selectivity for an amateur RTTY HF receiver?
100 Hz
300 Hz
6000 Hz
2400 Hz
Which of the following is a desirable amount of selectivity for an amateur SSB phone receiver?
1 kHz
2.4 kHz
4.2 kHz
4.8 kHz
What is an undesirable effect of using too wide a filter bandwidth in the IF section of a receiver?
Output-offset overshoot
Filter ringing
Thermal-noise distortion
Undesired signals may be heard
How does a narrow-band roofing filter affect receiver performance?
It improves sensitivity by reducing front end noise
It improves intelligibility by using low Q circuitry to reduce ringing
It improves dynamic range by attenuating strong signals near the receive frequency
All of these choices are correct
On which of the following frequencies What transmit frequency might a signal be transmitting which is generating a spurious image generate an image response signal in a receiver tuned to 14.300 MHz and which uses a 455 kHz IF frequency?
13.845 MHz
14.755 MHz
14.445 MHz
15.210 MHz
What is usually the primary source of noise that can be is heard from an HF receiver with an antenna connected?
Detector noise
Induction motor noise
Receiver front-end noise
Atmospheric noise
- NEW -
Which of the following is caused by missing codes in an SDR receiver's analog-to-digital converter?
Distortion
Overload
Loss of sensitivity
Excess output level
- NEW -
Which of the following has the largest effect on an SDR receiver's linearity?
CPU register width in bits
Anti-aliasing input filter bandwidth
RAM speed used for data storage
Analog-to-digital converter sample width in bits
Section E4D
Receiver performance characteristics: blocking dynamic range; intermodulation and cross-modulation interference; 3rd order intercept; desensitization; preselectorpreselection
Removed questions: 0
New questions: 0
Updated questions: 1
Total questions: 14
What is meant by the blocking dynamic range of a receiver?
The difference in dB between the noise floor and the level of an incoming signal which will cause 1 dB of gain compression
The minimum difference in dB between the levels of two FM signals which will cause one signal to block the other
The difference in dB between the noise floor and the third order intercept point
The minimum difference in dB between two signals which produce third order intermodulation products greater than the noise floor
Which of the following describes two problems caused by poor dynamic range in a communications receiver?
Cross-modulation of the desired signal and desensitization from strong adjacent signals
Oscillator instability requiring frequent retuning and loss of ability to recover the opposite sideband
Cross-modulation of the desired signal and insufficient audio power to operate the speaker
Oscillator instability and severe audio distortion of all but the strongest received signals
How can intermodulation interference between two repeaters occur?
When the repeaters are in close proximity and the signals cause feedback in the final amplifier of one or both transmitters
When the repeaters are in close proximity and the signals mix in the final amplifier of one or both transmitters
When the signals from the transmitters are reflected out of phase from airplanes passing overhead
When the signals from the transmitters are reflected in phase from airplanes passing overhead
Which of the following may reduce or eliminate intermodulation interference in a repeater caused by another transmitter operating in close proximity?
A band-pass filter in the feed line between the transmitter and receiver
A properly terminated circulator at the output of the transmitter
A Class C final amplifier
A Class D final amplifier
What transmitter frequencies would cause an intermodulation-product signal in a receiver tuned to 146.70 MHz when a nearby station transmits on 146.52 MHz?
146.34 MHz and 146.61 MHz
146.88 MHz and 146.34 MHz
146.10 MHz and 147.30 MHz
173.35 MHz and 139.40 MHz
What is the term for unwanted signals generated by the mixing of two or more signals?
Amplifier desensitization
Neutralization
Adjacent channel interference
Intermodulation interference
Which of the following describes the most significant effect of an off-frequency signal when it is causing cross-modulation interference to a desired signal?
A large increase in background noise
A reduction in apparent signal strength
The desired signal can no longer be heard
The off-frequency unwanted signal is heard in addition to the desired signal
What causes intermodulation in an electronic circuit?
Too little gain
Lack of neutralization
Nonlinear circuits or devices
Positive feedback
What is the purpose of the preselector in a communications receiver?
To store often-used frequencies
To provide a range of AGC time constants
To increase rejection of unwanted signals
To allow selection of the optimum RF amplifier device
What does a third-order intercept level of 40 dBm mean with respect to receiver performance?
Signals less than 40 dBm will not generate audible third-order intermodulation products
The receiver can tolerate signals up to 40 dB above the noise floor without producing third-order intermodulation products
A pair of 40 dBm signals will theoretically generate a third-order intermodulation product with the same level as the input signals
A pair of 1 mW input signals will produce a third-order intermodulation product which is 40 dB stronger than the input signal
Why are third-order intermodulation products created within a receiver of particular interest compared to other products?
The third-order product of two signals which are in the band of interest is also likely to be within the band
The third-order intercept is much higher than other orders
Third-order products are an indication of poor image rejection
Third-order intermodulation produces three products for every input signal within the band of interest
What is the term for the reduction in receiver sensitivity caused by a strong signal near the received frequency?
Desensitization
Quieting
Cross-modulation interference
Squelch gain rollback
Which of the following can cause receiver desensitization?
Audio gain adjusted too low
Strong adjacent- channel signals
Audio bias adjusted too high
Squelch gain misadjusted
Which of the following is a way to reduce the likelihood of receiver desensitization?
Decrease the RF bandwidth of the receiver
Raise the receiver IF frequency
Increase the receiver front end gain
Switch from fast AGC to slow AGC
Section E4E
Noise suppression: system noise; electrical appliance noise; line noise; locating noise sources; DSP noise reduction; noise blankers; grounding for signals
Removed questions: 0
New questions: 2
Updated questions: 1
Total questions: 16
Which of the following types of receiver noise can often be reduced by use of a receiver noise blanker?
Ignition noise
Broadband white noise
Heterodyne interference
All of these choices are correct
Which of the following types of receiver noise can often be reduced with a DSP noise filter?
Broadband white noise
Ignition noise
Power line noise
All of these choices are correct
Which of the following signals might a receiver noise blanker be able to remove from desired signals?
Signals which are constant at all IF levels
Signals which appear across a wide bandwidth
Signals which appear at one IF but not another
Signals which have a sharply peaked frequency distribution
How can conducted and radiated noise caused by an automobile alternator be suppressed?
By installing filter capacitors in series with the DC power lead and by installing a blocking capacitor in the field lead
By installing a noise suppression resistor and a blocking capacitor in both leads
By installing a high-pass filter in series with the radio's power lead and a low-pass filter in parallel with the field lead
By connecting the radio's power leads directly to the battery and by installing coaxial capacitors in line with the alternator leads
How can noise from an electric motor be suppressed?
By installing a high pass filter in series with the motor's power leads
By installing a brute-force AC-line filter in series with the motor leads
By installing a bypass capacitor in series with the motor leads
By using a ground-fault current interrupter in the circuit used to power the motor
What is a major cause of atmospheric static?
Solar radio frequency emissions
Thunderstorms
Geomagnetic storms
Meteor showers
How can you determine if line noise interference is being generated within your home?
By checking the power line voltage with a time domain reflectometer
By observing the AC power line waveform with an oscilloscope
By turning off the AC power line main circuit breaker and listening on a battery operated radio
By observing the AC power line voltage with a spectrum analyzer
What type of signal is picked up by electrical wiring near a radio antenna?
A common-mode signal at the frequency of the radio transmitter
An electrical-sparking signal
A differential-mode signal at the AC power line frequency
Harmonics of the AC power line frequency
What undesirable effect can occur when using an IF noise blanker?
Received audio in the speech range might have an echo effect
The audio frequency bandwidth of the received signal might be compressed
Nearby signals may appear to be excessively wide even if they meet emission standards
FM signals can no longer be demodulated
What is a common characteristic of interference caused by a touch controlled electrical device?
The interfering signal sounds like AC hum on an AM receiver or a carrier modulated by 60 Hz hum on a SSB or CW receiver
The interfering signal may drift slowly across the HF spectrum
The interfering signal can be several kHz in width and usually repeats at regular intervals across a HF band
All of these choices are correct
Which of the following is the most likely cause if you are hearing combinations of local AM broadcast signals within one or more of the MF or HF ham bands?
The broadcast station is transmitting an over-modulated signal
Nearby corroded metal joints are mixing and re-radiating the broadcast signals
You are receiving sky wave signals from a distant station
Your station receiver IF amplifier stage is defective
What is one disadvantage of using some types of automatic DSP notch-filters when attempting to copy CW signals?
TheA DSP filter can remove the desired signal at the same time as it removes interfering signals
Any nearby signal passing through the DSP system will overwhelm the desired signal
Received CW signals will appear to be modulated at the DSP clock frequency
Ringing in the DSP filter will completely remove the spaces between the CW characters
What might be the cause of a loud roaring or buzzing AC line interference that comes and goes at intervals?
Arcing contacts in a thermostatically controlled device
A defective doorbell or doorbell transformer inside a nearby residence
A malfunctioning illuminated advertising display
All of these choices are correct
What is one type of electrical interference that might be caused by the operation of a nearby personal computer?
A loud AC hum in the audio output of your station receiver
A clicking noise at intervals of a few seconds
The appearance of unstable modulated or unmodulated signals at specific frequencies
A whining type noise that continually pulses off and on
- NEW -
Which of the following can cause shielded cables to radiate or receive interference?
Low inductance ground connections at both ends of the shield
Common mode currents on the shield and conductors
Use of braided shielding material
Tying all ground connections to a common point resulting in differential mode currents in the shield
- NEW -
What current flows equally on all conductors of an unshielded multi-conductor cable?
Differential-mode current
Common-mode current
Reactive current only
Return current
Subelement E5
ELECTRICAL PRINCIPLES
Removed questions: 27
New questions: 21
Updated questions: 2
Total questions: 65
Section E5A
Resonance and Q: characteristics of resonant circuits;: series and parallel resonance; definitions and effects of Q; half-power bandwidth; phase relationships in reactive circuits
Removed questions: 5
New questions: 5
Updated questions: 0
Total questions: 17
REMOVED
What is the phase relationship between the current through and the voltage across a parallel resonant circuit at resonance?
The voltage leads the current by 90 degrees
The current leads the voltage by 90 degrees
The voltage and current are in phase
The voltage and current are 180 degrees out of phase
REMOVED
What is the half-power bandwidth of a parallel resonant circuit that has a resonant frequency of 1.8 MHz and a Q of 95?
18.9 kHz
1.89 kHz
94.5 kHz
9.45 kHz
REMOVED
What is the half-power bandwidth of a parallel resonant circuit that has a resonant frequency of 14.25 MHz and a Q of 187?
38.1 kHz
76.2 kHz
1.332 kHz
2.665 kHz
REMOVED
What is the resonant frequency of a series RLC circuit if R is 56 ohms, L is 40 microhenrys and C is 200 picofarads?
3.76 MHz
1.78 MHz
11.18 MHz
22.36 MHz
REMOVED
What is the resonant frequency of a parallel RLC circuit if R is 47 ohms, L is 25 microhenrys and C is 10 picofarads?
10.1 MHz
63.2 MHz
10.1 kHz
63.2 kHz
What can cause the voltage across reactances in series to be larger than the voltage applied to them?
Resonance
Capacitance
Conductance
Resistance
What is resonance in an electrical circuit?
The highest frequency that will pass current
The lowest frequency that will pass current
The frequency at which the capacitive reactance equals the inductive reactance
The frequency at which the reactive impedance equals the resistive impedance
What is the magnitude of the impedance of a series RLC circuit at resonance?
High, as compared to the circuit resistance
Approximately equal to capacitive reactance
Approximately equal to inductive reactance
Approximately equal to circuit resistance
What is the magnitude of the impedance of a circuit with a resistor, an inductor and a capacitor all in parallel, at resonance?
Approximately equal to circuit resistance
Approximately equal to inductive reactance
Low, as compared to the circuit resistance
Approximately equal to capacitive reactance
What is the magnitude of the current at the input of a series RLC circuit as the frequency goes through resonance?
Minimum
Maximum
R/L
L/R
What is the magnitude of the circulating current within the components of a parallel LC circuit at resonance?
It is at a minimum
It is at a maximum
It equals 1 divided by the quantity 2 times Pi, multiplied by the square root of inductance L multiplied by capacitance C
It equals 2 multiplied by Pi, multiplied by frequency "F", multiplied by inductance "L"
What is the magnitude of the current at the input of a parallel RLC circuit at resonance?
Minimum
Maximum
R/L
L/R
What is the phase relationship between the current through and the voltage across a series resonant circuit at resonance?
The voltage leads the current by 90 degrees
The current leads the voltage by 90 degrees
The voltage and current are in phase
The voltage and current are 180 degrees out of phase
- NEW -
How is the Q of an RLC parallel resonant circuit calculated?
Reactance of either the inductance or capacitance divided by the resistance
Reactance of either the inductance or capacitance multiplied by the resistance
Resistance divided by the reactance of either the inductance or capacitance
Reactance of the inductance multiplied by the reactance of the capacitance
- NEW -
How is the Q of an RLC series resonant circuit calculated?
Reactance of either the inductance or capacitance divided by the resistance
Reactance of either the inductance or capacitance times the resistance
Resistance divided by the reactance of either the inductance or capacitance
Reactance of the inductance times the reactance of the capacitance
What is the half-power bandwidth of a parallel resonant circuit that has a resonant frequency of 7.1 MHz and a Q of 150?
157.8 Hz
315.6 Hz
47.3 kHz
23.67 kHz
What is the half-power bandwidth of a parallel resonant circuit that has a resonant frequency of 3.7 MHz and a Q of 118?
436.6 kHz
218.3 kHz
31.4 kHz
15.7 kHz
- NEW -
What is an effect of increasing Q in a resonant circuit?
Fewer components are needed for the same performance
Parasitic effects are minimized
Internal voltages and circulating currents increase
Phase shift can become uncontrolled
What is the resonant frequency of a series RLC circuit if R is 22 ohms, L is 50 microhenrys and C is 40 picofarads?
44.72 MHz
22.36 MHz
3.56 MHz
1.78 MHz
- NEW -
Which of the following can increase Q for inductors and capacitors?
Lower losses
Lower reactance
Lower self-resonant frequency
Higher self-resonant frequency
What is the resonant frequency of a parallel RLC circuit if R is 33 ohms, L is 50 microhenrys and C is 10 picofarads?
23.5 MHz
23.5 kHz
7.12 kHz
7.12 MHz
- NEW -
What is the result of increasing the Q of an impedance-matching circuit?
Matching bandwidth is decreased
Matching bandwidth is increased
Matching range is increased
It has no effect on impedance matching
Section E5B
Time constants and phase relationships: RLC time constants; definition; time constants in RL and RC circuits; phase angle between voltage and current; phase angles of series RLC; phase angle of inductance vs susceptance; admittance and susceptanceand parallel circuits
Removed questions: 5
New questions: 5
Updated questions: 0
Total questions: 13
REMOVED
The capacitor in an RC circuit is discharged to what percentage of the starting voltage after two time constants?
86.5%
63.2%
36.8%
13.5%
REMOVED
How long does it take for an initial charge of 20 V DC to decrease to 7.36 V DC in a 0.01-microfarad capacitor when a 2-megohm resistor is connected across it?
0.02 seconds
0.04 seconds
20 seconds
40 seconds
REMOVED
How long does it take for an initial charge of 800 V DC to decrease to 294 V DC in a 450-microfarad capacitor when a 1-megohm resistor is connected across it?
4.50 seconds
9 seconds
450 seconds
900 seconds
REMOVED
What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 75 ohms, R is 100 ohms, and XL is 50 ohms?
76 degrees with the voltage lagging the current
14 degrees with the voltage leading the current
14 degrees with the voltage lagging the current
76 degrees with the voltage leading the current
REMOVED
What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 250 ohms, R is 1 kilohm, and XL is 500 ohms?
81.47 degrees with the voltage lagging the current
81.47 degrees with the voltage leading the current
14.04 degrees with the voltage lagging the current
14.04 degrees with the voltage leading the current
What is the term for the time required for the capacitor in an RC circuit to be charged to 63.2% of the applied voltage?
An exponential rate of one
One time constant
One exponential period
A time factor of one
What is the term for the time it takes for a charged capacitor in an RC circuit to discharge to 36.8% of its initial voltage?
One discharge period
An exponential discharge rate of one
A discharge factor of one
One time constant
- NEW -
What happens to the phase angle of a reactance when it is converted to a susceptance?
It is unchanged
The sign is reversed
It is shifted by 90 degrees
The susceptance phase angle is the inverse of the reactance phase angle
What is the time constant of a circuit having two 220- microfarad capacitors and two 1- megohm resistors, all in parallel?
55 seconds
110 seconds
440 seconds
220 seconds
- NEW -
What happens to the magnitude of a reactance when it is converted to a susceptance?
It is unchanged
The sign is reversed
It is shifted by 90 degrees
The magnitude of the susceptance is the reciprocal of the magnitude of the reactance
- NEW -
What is susceptance?
The magnetic impedance of a circuit
The ratio of magnetic field to electric field
The inverse of reactance
A measure of the efficiency of a transformer
What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 500 ohms, R is 1 kilohm, and XL is 250 ohms?
68.2 degrees with the voltage leading the current
14.0 degrees with the voltage leading the current
14.0 degrees with the voltage lagging the current
68.2 degrees with the voltage lagging the current
What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 100 ohms, R is 100 ohms, and XL is 75 ohms?
14 degrees with the voltage lagging the current
14 degrees with the voltage leading the current
76 degrees with the voltage leading the current
76 degrees with the voltage lagging the current
What is the relationship between the current through a capacitor and the voltage across a capacitor?
Voltage and current are in phase
Voltage and current are 180 degrees out of phase
Voltage leads current by 90 degrees
Current leads voltage by 90 degrees
What is the relationship between the current through an inductor and the voltage across an inductor?
Voltage leads current by 90 degrees
Current leads voltage by 90 degrees
Voltage and current are 180 degrees out of phase
Voltage and current are in phase
What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 25 ohms, R is 100 ohms, and XL is 50 ohms?
14 degrees with the voltage lagging the current
14 degrees with the voltage leading the current
76 degrees with the voltage lagging the current
76 degrees with the voltage leading the current
- NEW -
What is admittance?
The inverse of impedance
The term for the gain of a field effect transistor
The turns ratio of a transformer
The unit used for Q factor
- NEW -
What letter is commonly used to represent susceptance?
G
X
Y
B
Section E5C
Impedance plotsCoordinate systems and phasors in electronics: Rectangular Coordinates; Polar Coordinates; Phasorscoordinate systems: plotting impedances in polar coordinates; rectangular coordinates
Removed questions: 13
New questions: 7
Updated questions: 1
Total questions: 17
REMOVED
In polar coordinates, what is the impedance of a network consisting of a 100-ohm-reactance inductor in series with a 100-ohm resistor?
121 ohms at an angle of 35 degrees
141 ohms at an angle of 45 degrees
161 ohms at an angle of 55 degrees
181 ohms at an angle of 65 degrees
REMOVED
In polar coordinates, what is the impedance of a network consisting of a 100-ohm-reactance inductor, a 100-ohm-reactance capacitor, and a 100-ohm resistor, all connected in series?
100 ohms at an angle of 90 degrees
10 ohms at an angle of 0 degrees
10 ohms at an angle of 90 degrees
100 ohms at an angle of 0 degrees
REMOVED
In polar coordinates, what is the impedance of a network consisting of a 300-ohm-reactance capacitor, a 600-ohm-reactance inductor, and a 400-ohm resistor, all connected in series?
500 ohms at an angle of 37 degrees
900 ohms at an angle of 53 degrees
400 ohms at an angle of 0 degrees
1300 ohms at an angle of 180 degrees
REMOVED
In polar coordinates, what is the impedance of a network consisting of a 400-ohm-reactance capacitor in series with a 300-ohm resistor?
240 ohms at an angle of 36.9 degrees
240 ohms at an angle of -36.9 degrees
500 ohms at an angle of 53.1 degrees
500 ohms at an angle of -53.1 degrees
REMOVED
In polar coordinates, what is the impedance of a network consisting of a 400-ohm-reactance inductor in parallel with a 300-ohm resistor?
240 ohms at an angle of 36.9 degrees
240 ohms at an angle of -36.9 degrees
500 ohms at an angle of 53.1 degrees
500 ohms at an angle of -53.1 degrees
REMOVED
In polar coordinates, what is the impedance of a network consisting of a 100-ohm-reactance capacitor in series with a 100-ohm resistor?
121 ohms at an angle of -25 degrees
191 ohms at an angle of -85 degrees
161 ohms at an angle of -65 degrees
141 ohms at an angle of -45 degrees
REMOVED
In polar coordinates, what is the impedance of a network comprised of a 100-ohm-reactance capacitor in parallel with a 100-ohm resistor?
31 ohms at an angle of -15 degrees
51 ohms at an angle of -25 degrees
71 ohms at an angle of -45 degrees
91 ohms at an angle of -65 degrees
REMOVED
In polar coordinates, what is the impedance of a network comprised of a 300-ohm-reactance inductor in series with a 400-ohm resistor?
400 ohms at an angle of 27 degrees
500 ohms at an angle of 37 degrees
500 ohms at an angle of 47 degrees
700 ohms at an angle of 57 degrees
REMOVED
In polar coordinates, what is the impedance of a circuit of 100 -j100 ohms impedance?
141 ohms at an angle of -45 degrees
100 ohms at an angle of 45 degrees
100 ohms at an angle of -45 degrees
141 ohms at an angle of 45 degrees
REMOVED
In polar coordinates, what is the impedance of a circuit that has an admittance of 7.09 millisiemens at 45 degrees?
5.03 E-06 ohms at an angle of 45 degrees
141 ohms at an angle of -45 degrees
19,900 ohms at an angle of -45 degrees
141 ohms at an angle of 45 degrees
REMOVED
In rectangular coordinates, what is the impedance of a circuit that has an admittance of 5 millisiemens at -30 degrees?
173 - j100 ohms
200 + j100 ohms
173 + j100 ohms
200 - j100 ohms
REMOVED
In polar coordinates, what is the impedance of a series circuit consisting of a resistance of 4 ohms, an inductive reactance of 4 ohms, and a capacitive reactance of 1 ohm?
6.4 ohms at an angle of 53 degrees
5 ohms at an angle of 37 degrees
5 ohms at an angle of 45 degrees
10 ohms at an angle of -51 degrees
REMOVED
In rectangular coordinates, what is the impedance of a network consisting of a 10-microhenry inductor in series with a 40-ohm resistor at 500 MHz?
40 + j31,400
40 - j31,400
31,400 + j40
31,400 - j40
- NEW -
Which of the following represents a capacitive reactance in rectangular notation?
-jX
+jX
X
Omega
- NEW -
How are impedances described in polar coordinates?
By X and R values
By real and imaginary parts
By phase angle and amplitude
By Y and G values
- NEW -
Which of the following represents an inductive reactance in polar coordinates?
A positive real part
A negative real part
A positive phase angle
A negative phase angle
- NEW -
Which of the following represents a capacitive reactance in polar coordinates?
A positive real part
A negative real part
A positive phase angle
A negative phase angle
- NEW -
What is the name of the diagram used to show the phase relationship between impedances at a given frequency?
Venn diagram
Near field diagram
Phasor diagram
Far field diagram
- NEW -
What does the impedance 50-j25 represent?
50 ohms resistance in series with 25 ohms inductive reactance
50 ohms resistance in series with 25 ohms capacitive reactance
25 ohms resistance in series with 50 ohms inductive reactance
25 ohms resistance in series with 50 ohms capacitive reactance
- NEW -
What is a vector?
The value of a quantity that changes over time
A quantity with both magnitude and an angular component
The inverse of the tangent function
The inverse of the sine function
was E5C14
What coordinate system is often used to display the phase angle of a circuit containing resistance, inductive and/or capacitive reactance?
Maidenhead grid
Faraday grid
Elliptical coordinates
Polar coordinates
When using rectangular coordinates to graph the impedance of a circuit, what does the horizontal axis represent?
Resistive component
Reactive component
The sum of the reactive and resistive components
The difference between the resistive and reactive components
When using rectangular coordinates to graph the impedance of a circuit, what does the vertical axis represent?
Resistive component
Reactive component
The sum of the reactive and resistive components
The difference between the resistive and reactive components
What do the two numbers represent that are used to define a point on a graph using rectangular coordinates represent??
The magnitude and phase of the point
The sine and cosine values
The coordinate values along the horizontal and vertical axes
The tangent and cotangent values
If you plot the impedance of a circuit using the rectangular coordinate system and find the impedance point falls on the right side of the graph on the horizontal axis, what do you know about the circuit?
It has to be a direct current circuit
It contains resistance and capacitive reactance
It contains resistance and inductive reactance
It is equivalent to a pure resistance
What coordinate system is often used to display the resistive, inductive, and/or capacitive reactance components of an impedance?
Maidenhead grid
Faraday grid
Elliptical coordinates
Rectangular coordinates
was E5C19
Which point on Figure E5-2 best represents thatthe impedance of a series circuit consisting of a 400 ohm resistor and a 38 picofarad capacitor at 14 MHz?
Point 2
Point 4
Point 5
Point 6
was E5C20
Which point in Figure E5-2 best represents the impedance of a series circuit consisting of a 300 ohm resistor and an 18 microhenry inductor at 3.505 MHz?
Point 1
Point 3
Point 7
Point 8
was E5C21
Which point on Figure E5-2 best represents the impedance of a series circuit consisting of a 300 ohm resistor and a 19 picofarad capacitor at 21.200 MHz?
Point 1
Point 3
Point 7
Point 8
was E5C23
Which point on Figure E5-2 best represents the impedance of a series circuit consisting of a 300- ohm resistor, a 0.64-microhenry inductor and an 85-picofarad capacitor at 24.900 MHz?
Point 1
Point 3
Point 5
Point 8
Section E5D
AC and RF energy in real circuits: skin effect; electrostatic and electromagnetic fields; reactive power; power factor; electrical length of conductors at UHF and microwave frequenciescoordinate systems
Removed questions: 4
New questions: 4
Updated questions: 1
Total questions: 18
REMOVED
Why is the resistance of a conductor different for RF currents than for direct currents?
Because the insulation conducts current at high frequencies
Because of the Heisenburg Effect
Because of skin effect
Because conductors are non-linear devices
REMOVED
What device is used to store electrical energy in an electrostatic field?
A battery
A transformer
A capacitor
An inductor
REMOVED
What unit measures electrical energy stored in an electrostatic field?
Coulomb
Joule
Watt
Volt
REMOVED
Which of the following creates a magnetic field?
Potential differences between two points in space
Electric current
A charged capacitor
A battery
What is the result of skin effect?
As frequency increases, RF current flows in a thinner layer of the conductor, closer to the surface
As frequency decreases, RF current flows in a thinner layer of the conductor, closer to the surface
Thermal effects on the surface of the conductor increase the impedance
Thermal effects on the surface of the conductor decrease the impedance
- NEW -
Why is it important to keep lead lengths short for components used in circuits for VHF and above?
To increase the thermal time constant
To avoid unwanted inductive reactance
To maintain component lifetime
All of these choices are correct
- NEW -
What is microstrip?
Lightweight transmission line made of common zip cord
Miniature coax used for low power applications
Short lengths of coax mounted on printed circuit boards to minimize time delay between microwave circuits
Precision printed circuit conductors above a ground plane that provide constant impedance interconnects at microwave frequencies
- NEW -
Why are short connections necessary at microwave frequencies?
To increase neutralizing resistance
To reduce phase shift along the connection
Because of ground reflections
To reduce noise figure
- NEW -
Which parasitic characteristic increases with conductor length?
Inductance
Permeability
Permittivity
Malleability
In what direction is the magnetic field oriented about a conductor in relation to the direction of electron flow?
In the same direction as the current
In a direction opposite to the current
In all directions; omni-directionalomnidirectional
In a direction determined by the left-hand rule
What determines the strength of athe magnetic field around a conductor?
The resistance divided by the current
The ratio of the current to the resistance
The diameter of the conductor
The amount of current flowing through the conductor
What type of energy is stored in an electromagnetic or electrostatic field?
Electromechanical energy
Potential energy
Thermodynamic energy
Kinetic energy
What happens to reactive power in an AC circuit that has both ideal inductors and ideal capacitors?
It is dissipated as heat in the circuit
It is repeatedly exchanged between the associated magnetic and electric fields, but is not dissipated
It is dissipated as kinetic energy in the circuit
It is dissipated in the formation of inductive and capacitive fields
How can the true power be determined in an AC circuit where the voltage and current are out of phase?
By multiplying the apparent power times the power factor
By dividing the reactive power by the power factor
By dividing the apparent power by the power factor
By multiplying the reactive power times the power factor
What is the power factor of an R-L circuit having a 60 degree phase angle between the voltage and the current?
1.414
0.866
0.5
1.73
How many watts are consumed in a circuit having a power factor of 0.2 if the input is 100-V AC VAC at 4 amperes?
400 watts
80 watts
2000 watts
50 watts
How much power is consumed in a circuit consisting of a 100 ohm resistor in series with a 100 ohm inductive reactance drawing 1 ampere?
70.7 Watts
100 Watts
141.4 Watts
200 Watts
What is reactive power?
Wattless, nonproductive power
Power consumed in wire resistance in an inductor
Power lost because of capacitor leakage
Power consumed in circuit Q
What is the power factor of an RLR-L circuit having a 45 degree phase angle between the voltage and the current?
0.866
1.0
0.5
0.707
What is the power factor of an RLR-L circuit having a 30 degree phase angle between the voltage and the current?
1.73
0.5
0.866
0.577
How many watts are consumed in a circuit having a power factor of 0.6 if the input is 200V AC 200VAC at 5 amperes?
200 watts
1000 watts
1600 watts
600 watts
How many watts are consumed in a circuit having a power factor of 0.71 if the apparent power is 500VA?500 VA?
What are the majority charge carriers in P-type semiconductor material?
Free neutrons
Free protons
Holes
Free electrons
REMOVED
In Figure E6-1, what is the schematic symbol for a PNP transistor?
1
2
4
5
In what application is gallium arsenide used as a semiconductor material in preference to germanium or silicon?
In high-current rectifier circuits
In high-power audio circuits
AtIn microwave circuitsfrequencies
AtIn very low frequency RF circuits
Which of the following semiconductor materials contains excess free electrons?
N-type
P-type
Bipolar
Insulated gate
- NEW -
Why does a PN-junction diode not conduct current when reverse biased?
Only P-type semiconductor material can conduct current
Only N-type semiconductor material can conduct current
Holes in P-type material and electrons in the N-type material are separated by the applied voltage, widening the depletion region
Excess holes in P-type material combine with the electrons in N-type material, converting, the entire diode into an insulator
What is the name given to an impurity atom that adds holes to a semiconductor crystal structure?
Insulator impurity
N-type impurity
Acceptor impurity
Donor impurity
What is the alpha of a bipolar junction transistor?
The change of collector current with respect to base current
The change of base current with respect to collector current
The change of collector current with respect to emitter current
The change of collector current with respect to gate current
What is the beta of a bipolar junction transistor?
The frequency at which the current gain is reduced to 1
The change in collector current with respect to base current
The breakdown voltage of the base to collector junction
The switching speed of the transistor
was E4A10
Which of the following tests establishes indicates that a silicon NPN junction transistor is biased on?
Measure baseBase-to-emitter resistance with an ohmmeter; it should be of approximately 6 to 7 ohms
Measure baseBase-to-emitter resistance with an ohmmeter; it should be of approximately 0.6 to 0.7 ohms
Measure baseBase-to-emitter voltage with a voltmeter; it should be of approximately 6 to 7 volts
Measure baseBase-to-emitter voltage with a voltmeter; it should be of approximately 0.6 to 0.7 volts
What term indicates the frequency at which the grounded-base current gain of a transistor has decreased to 0.7 of the gain obtainable at 1 kHz?
Corner frequency
Alpha rejection frequency
Beta cutoff frequency
Alpha cutoff frequency
What is a depletion-mode FET?
An FET that exhibits a current flow between source and drain when no gate voltage is applied
An FET that has no current flow between source and drain when no gate voltage is applied
Any FET without a channel
Any FET for which holes are the majority carriers
In Figure E6-2, what is the schematic symbol for an N-channel dual-gate MOSFET?
2
4
5
6
In Figure E6-2, what is the schematic symbol for a P-channel junction FET?
1
2
3
6
Why do many MOSFET devices have internally connected Zener diodes on the gates?
To provide a voltage reference for the correct amount of reverse-bias gate voltage
To protect the substrate from excessive voltages
To keep the gate voltage within specifications and prevent the device from overheating
To reduce the chance of the gate insulation being punctured by static discharges or excessive voltages
What do the initials CMOS stand for?
Common Mode Oscillating System
Complementary Mica-Oxide Silicon
Complementary Metal-Oxide Semiconductor
Common Mode Organic Silicon
How does DC input impedance at the gate of a field-effect transistor compare with the DC input impedance of a bipolar transistor?
They are both low impedance
An FET has low input impedance; a bipolar transistor has high input impedance
An FET has high input impedance; a bipolar transistor has low input impedance
They are both high impedance
Which of the following semiconductor materialsmaterial contains an excess of holes in the outer shell of electrons?
N-type
P-type
Superconductor-type
Bipolar-type
What are the majority charge carriers in N-type semiconductor material?
Holes
Free electrons
Free protons
Free neutrons
What are the names of the three terminals of a field-effect transistor?
Gate 1, gate 2, drain
Emitter, base, collector
Emitter, base 1, base 2
Gate, drain, source
Section E6B
Semiconductor diodesDiodes
Removed questions: 0
New questions: 0
Updated questions: 0
Total questions: 13
What is the most useful characteristic of a Zener diode?
A constant current drop under conditions of varying voltage
A constant voltage drop under conditions of varying current
A negative resistance region
An internal capacitance that varies with the applied voltage
What is an important characteristic of a Schottky diode as compared to an ordinary silicon diode when used as a power supply rectifier?
Much higher reverse voltage breakdown
Controlled reverse avalanche voltage
Enhanced carrier retention time
Less forward voltage drop
What special type of diode is capable of both amplification and oscillation?
Point contact
Zener
Tunnel
Junction
What type of semiconductor device is designed for use as a voltage-controlled capacitor?
Varactor diode
Tunnel diode
Silicon-controlled rectifier
Zener diode
What characteristic of a PIN diode makes it useful as an RF switch or attenuator?
Extremely high reverse breakdown voltage
Ability to dissipate large amounts of power
Reverse bias controls its forward voltage drop
A large region of intrinsic material
Which of the following is a common use of a hot-carrier diode?
As balanced mixers in FM generation
As a variable capacitance in an automatic frequency control circuit
As a constant voltage reference in a power supply
As a VHF / /UHF mixer or detector
What is the failure mechanism when a junction diode fails due to excessive current?
Excessive inverse voltage
Excessive junction temperature
Insufficient forward voltage
Charge carrier depletion
Which of the following describes a type of semiconductor diode?
Metal-semiconductor junction
Electrolytic rectifier
CMOS-field effect
Thermionic emission diode
What is a common use for point contact diodes?
As a constant current source
As a constant voltage source
As an RF detector
As a high voltage rectifier
In Figure E6-3, what is the schematic symbol for a light-emitting diode?
1
5
6
7
What is used to control the attenuation of RF signals by a PIN diode?
Forward DC bias current
A sub-harmonic pump signal
Reverse voltage larger than the RF signal
Capacitance of an RF coupling capacitor
What is one common use for PIN diodes?
As a constant current source
As a constant voltage source
As an RF switch
As a high voltage rectifier
What type of bias is required for an LED to emit light?
Reverse bias
Forward bias
Zero bias
Inductive bias
Section E6C
Integrated circuits: TTL Digital ICs: Families of digital ICs; gates; Programmable Logic Devices (PLDs)integrated circuits; CMOS digital integrated circuits; gates
Removed questions: 4
New questions: 5
Updated questions: 3
Total questions: 14
REMOVED
What is the recommended power supply voltage for TTL series integrated circuits?
12 volts
1.5 volts
5 volts
13.6 volts
REMOVED
What logic state do the inputs of a TTL device assume if they are left open?
A logic-high state
A logic-low state
The device becomes randomized and will not provide consistent high or low-logic states
Open inputs on a TTL device are ignored
REMOVED
In Figure E6-5, what is the schematic symbol for a NAND gate?
1
2
3
4
REMOVED
In Figure E6-5, what is the schematic symbol for a NOR gate?
1
2
3
4
- NEW -
What is the function of hysteresis in a comparator?
To prevent input noise from causing unstable output signals
To allow the comparator to be used with AC input signal
To cause the output to change states continually
To increase the sensitivity
- NEW -
What happens when the level of a comparator's input signal crosses the threshold?
The IC input can be damaged
The comparator changes its output state
The comparator enters latch-up
The feedback loop becomes unstable
Which of the following describes What is tri-state logic?
Logic devices with 0, 1, and high impedance output states
Logic devices that utilize ternary math
Low power logic devices designed to operate at 3 volts
Proprietary logic devices manufactured by Tri-State Devices
Which of the following What is the primary advantage of tri-state logic?
Low power consumption
Ability to connect many device outputs to a common bus
High speed operation
More efficient arithmetic operations
Which of the following What is an advantage of CMOS logic devices over TTL devices?
Differential output capability
Lower distortion
Immune to damage from static discharge
Lower power consumption
Why do CMOS digital integrated circuits have high immunity to noise on the input signal or power supply?
Larger bypass capacitors are used in CMOS circuit design
The input switching threshold is about two times the power supply voltage
The input switching threshold is about one-half the power supply voltage
Input signals are stronger
- NEW -
What best describes a pull-up or pull-down resistor?
A resistor in a keying circuit used to reduce key clicks
A resistor connected to the positive or negative supply line used to establish a voltage when an input or output is an open circuit
A resistor that insures that an oscillator frequency does not drive lower over time
A resistor connected to an op-amp output that only functions when the logic output is false
was E6C07
In Figure E6-5, what is the schematic symbol for an ANDa NAND gate?
1
2
3
4
- NEW -
What is a Programmable Logic Device (PLD)?
A device to control industrial equipment
A programmable collection of logic gates and circuits in a single integrated circuit
Programmable equipment used for testing digital logic integrated circuits
An algorithm for simulating logic functions during circuit design
was E6C09
In Figure E6-5, what is the schematic symbol for an ORa NOR gate?
21
32
43
64
In Figure E6-5, what is the schematic symbol for the NOT operation (inverter)?
2
4
5
6
What is BiCMOS logic?
A logic device with two CMOS circuits per package
AnA FET logic family based on bimetallic semiconductors
A logic family based on bismuth CMOS devices
An integrated circuit logic family using both bipolar and CMOS transistors
Which of the following is an advantage of BiCMOS logic?
Its simplicity results in much less expensive devices than standard CMOS
It is totally immune to electrostatic damage
It has the high input impedance of CMOS and the low output impedance of bipolar transistors
All of these choices are correct
- NEW -
What is the primary advantage of using a Programmable Gate Array (PGA) in a logic circuit?
Many similar gates are less expensive than a mixture of gate types
Complex logic functions can be created in a single integrated circuit
The time it takes for an image to appear after the electron beam is turned on
The relative brightness of the display under varying conditions of ambient light
The ability of the display to remain in focus under varying conditions
The length of time the image remains on the screen after the beam is turned off
REMOVED
Exceeding what design rating can cause a cathode ray tube (CRT) to generate X-rays?
The heater voltage
The anode voltage
The operating temperature
The operating frequency
REMOVED
What function does a charge-coupled device (CCD) serve in a modern video camera?
It stores photogenerated charges as signals corresponding to pixels
It generates the horizontal pulses needed for electron beam scanning
It focuses the light used to produce a pattern of electrical charges corresponding to the image
It combines audio and video information to produce a composite RF signal
REMOVED
What type of CRT deflection is better when high-frequency waveforms are to be displayed on the screen?
Electromagnetic
Tubular
Radar
Electrostatic
REMOVED
Which is NOT true of a charge-coupled device (CCD)?
It uses a combination of analog and digital circuitry
It can be used to make an audio delay line
It is commonly used as an analog-to-digital converter
It samples and stores analog signals
REMOVED
What is the principle advantage of liquid-crystal display (LCD) devices over other types of display devices?
They consume less power
They can display changes instantly
They are visible in all light conditions
They can be easily interchanged with other display devices
was E6D12
How many turns will be required to produce a 5-microhenry inductor using a powdered-iron toroidal core that has an inductance index (A L) value of 40 microhenrys/100 turns?
35 turns
13 turns
79 turns
141 turns
was E6E10
What is the equivalent circuit of a quartz crystal?
Motional capacitance, motional inductance, and loss resistance in series, all in parallel with a shunt capacitancecapacitor representing electrode and stray capacitance
Motional capacitance, motional inductance, loss resistance, and a capacitor representing electrode and stray capacitance all in parallel
Motional capacitance, motional inductance, loss resistance, and a capacitor representrepresenting electrode and stray capacitance all in series
Motional inductance and loss resistance in series, paralleled with motional capacitance and a capacitor representing electrode and stray capacitance
was E6E03
What is oneWhich of the following is an aspect of the piezoelectric effect?
PhysicalMechanical deformation of a crystal material by the application of a voltage
Mechanical deformation of a crystal material by the application of a magnetic field
The generation Generation of electrical energy byin the applicationpresence of light
Reversed conduction states when a P-N junction is exposed to Increased conductivity in the presence of light
- NEW -
Which materials are commonly used as a slug core in a variable inductor?
Polystyrene and polyethylene
Ferrite and brass
Teflon and Delrin
Cobalt and aluminum
was E6D16
What is one reason for using ferrite toroidscores rather than powdered-iron toroids in an inductor?
Ferrite toroids generally have lower initial permeabilitypermeabilities
Ferrite toroids generally have better temperature stability
Ferrite toroids generally require fewer turns to produce a given inductance value
Ferrite toroids are easier to use with surface mount technology
What core material property determines the inductance of a toroidal inductor?
Thermal impedance
Resistance
Reactivity
Permeability
What is the usable frequency range of inductors that use toroidal cores, assuming a correct selection of core material for the frequency being used?
From a few kHz to no more than 30 MHz
From less than 20 Hz to approximately 300 MHz
From approximately 10 Hz to no more than 3000 kHz
From about 100 kHz to at least 1000 GHz
What is one important reason for using powdered-iron toroidscores rather than ferrite toroidscores in an inductor?
Powdered-iron toroidscores generally have greater initial permeability
Powdered-iron toroidscores generally maintain their characteristics at higher currents
Powdered-iron toroidscores generally require fewer turns to produce a given inductance value
Powdered-iron cores use smaller diameter wire for the same inductancetoroids have higher power handling capacity
What devices are commonly used as VHF and UHF parasitic suppressors at the input and output terminals of a transistor HF amplifier?transistorized HF amplifiers?
Electrolytic capacitors
Butterworth filters
Ferrite beads
Steel-core toroids
What is a primary advantage of using a toroidal core instead of a solenoidal core in an inductor?
Toroidal cores confine most of the magnetic field within the core material
Toroidal cores make it easier to couple the magnetic energy into other components
Toroidal cores exhibit greater hysteresis
Toroidal cores have lower Q characteristics
How many turns will be required to produce a 1-mH inductor using a ferrite toroidal core that has an inductance index (A L) value of 523 millihenrys/1000 turns?
2 turns
4 turns
43 turns
229 turns
- NEW -
What is the definition of saturation in a ferrite core inductor?
The inductor windings are over coupled
The inductor's voltage rating is exceeded causing a flashover
The ability of the inductor's core to store magnetic energy has been exceeded
Adjacent inductors become over-coupled
- NEW -
What is the primary cause of inductor self-resonance?
Inter-turn capacitance
The skin effect
Inductive kickback
Non-linear core hysteresis
- NEW -
Which type of slug material decreases inductance when inserted into a coil?
Ceramic
Brass
Ferrite
Powdered-iron
- NEW -
What is current in the primary winding of a transformer called if no load is attached to the secondary?
Magnetizing current
Direct current
Excitation current
Stabilizing current
- NEW -
What is the common name for a capacitor connected across a transformer secondary that is used to absorb transient voltage spikes?
Clipper capacitor
Trimmer capacitor
Feedback capacitor
Snubber capacitor
- NEW -
Why should core saturation of a conventional impedance matching transformer be avoided?
Harmonics and distortion could result
Magnetic flux would increase with frequency
RF susceptance would increase
Temporary changes of the core permeability could result
Section E6E
Piezoelectric crystals and Analog ICs: MMICs, CCDs, Device packages: quartz crystal oscillators and crystal filters); monolithic amplifiers
Removed questions: 0
New questions: 5
Updated questions: 1
Total questions: 12
was E6D03
Which of the following is true of a charge-coupled device (CCD)?
Its phase shift changes rapidly with frequency
It is a CMOS analog-to-digital converter
It samples an analog signal and passes it in stages from the input to the output
It is used in a battery charger circuit
- NEW -
Which of the following device packages is a through-hole type?
DIP
PLCC
Ball grid array
SOT
was E6E11
Which of the following materials is likely to provide the highest frequency of operation when used in MMICs?
Silicon
Silicon nitride
Silicon dioxide
Gallium nitride
WhatWhich is the most common input and output impedance of circuits that use MMICs?
50 ohms
300 ohms
450 ohms
10 ohms
Which of the following noise figure values is typical of a low-noise UHF preamplifier?
2 dB
-10 dB
44 dBm
-20 dBm
What characteristics of the MMIC make it a popular choice for VHF through microwave circuits?
The ability to retrieve information from a single signal even in the presence of other strong signals.
Plate current that is controlled by a control grid
Nearly infinite gain, very high input impedance, and very low output impedance
Controlled gain, low noise figure, and constant input and output impedance over the specified frequency range
Which of the following techniques is typically used to construct a MMIC-based microwave amplifier?
Ground-plane construction
Microstrip construction
Point-to-point construction
Wave-soldering construction
How is voltage from a power- supply voltage normally furnished to the most common type of monolithic microwave integrated circuit (MMIC)?
Through a resistor and/or RF choke connected to the amplifier output lead
MMICs require no operating bias
Through a capacitor and RF choke connected to the amplifier input lead
Directly to the bias- voltage (VCC IN) lead
- NEW -
Which of the following component package types would be most suitable for use at frequencies above the HF range?
TO-220
Axial lead
Radial lead
Surface mount
- NEW -
What is the packaging technique in which leadless components are soldered directly to circuit boards?
Direct soldering
Virtual lead mounting
Stripped lead
Surface mount
- NEW -
What is a characteristic of DIP packaging used for integrated circuits?
Package mounts in a direct inverted position
Low leakage doubly insulated package
Two chips in each package (Dual In Package)
A total of two rows of connecting pins placed on opposite sides of the package (Dual In-line Package)
- NEW -
Why are high-power RF amplifier ICs and transistors sometimes mounted in ceramic packages?
High-voltage insulating ability
Better dissipation of heat
Enhanced sensitivity to light
To provide a low-pass frequency response
Section E6F
Optical components and power systems: photoconductive principles and effects, photovoltaic systems, optical couplers, optical sensors, and optoisolators; LCDs
Removed questions: 0
New questions: 1
Updated questions: 2
Total questions: 14
What is photoconductivity?
The conversion of photon energy to electromotive energy
The increased conductivity of an illuminated semiconductor
The conversion of electromotive energy to photon energy
The decreased conductivity of an illuminated semiconductor
What happens to the conductivity of a photoconductive material when light shines on it?
It increases
It decreases
It stays the same
It becomes unstable
What is the most common configuration of an optoisolator or optocoupler?
A lens and a photomultiplier
A frequency modulated helium-neon laser
An amplitude modulated helium-neon laser
An LED and a phototransistor
What is the photovoltaic effect?
The conversion of voltage to current when exposed to light
The conversion of light to electrical energy
The conversion of electrical energy to mechanical energy
The tendency of a battery to discharge when used outside
Which of the following describes an optical shaft encoder?
A device which detects rotation of a control by interrupting a light source with a patterned wheel
A device which measures the strength of a beam of light using analog to digital conversion
A digital encryption device often used to encrypt spacecraft control signals
A device for generating RTTY signals by means of a rotating light source.
Which of these materials is affected the most by photoconductivity?
A crystalline semiconductor
An ordinary metal
A heavy metal
A liquid semiconductor
What is a solid state relay?
A relay using transistors to drive the relay coil
A device that uses semiconductor devices semiconductors to implement the functions of an electromechanical relay
A mechanical relay that latches in the on or off state each time it is pulsed
A passive delay line
Why are optoisolators often used in conjunction with solid state circuits when switching 120VAC?120 VAC?
Optoisolators provide a low impedance link between a control circuit and a power circuit
Optoisolators provide impedance matching between the control circuit and power circuit
Optoisolators provide a very high degree of electrical isolation between a control circuit and the circuit being switched
Optoisolators eliminate the effects of reflected light in the control circuit
What is the efficiency of a photovoltaic cell?
The output RF power divided by the input dcDC power
The effective payback period
The open-circuit voltage divided by the short-circuit current under full illumination
The relative fraction of light that is converted to current
What is the most common type of photovoltaic cell used for electrical power generation?
Selenium
Silicon
Cadmium Sulfide
Copper oxide
Which of the following What is the approximate open-circuit voltage produced by a fully-illuminated silicon photovoltaic cell?
0.1 V
0.5 V
1.5 V
12 V
What absorbs the energy from light falling on a photovoltaic cell?
Protons
Photons
Electrons
Holes
was E6D05
What is a liquid- crystal display (LCD)?
A modern replacement for a quartz crystal oscillator which displays its fundamental frequency
A display usingutilizing a crystalline liquid which, in conjunction with and polarizing filters, which becomes opaque when voltage is applied
A frequency-determining unit for a transmitter or receiver
A display that uses a glowing liquid to remain brightly lit in dim light
- NEW -
Which of the following is true of LCD displays?
They are hard to view in high ambient light conditions
They may be hard view through polarized lenses
They only display alphanumeric symbols
All of these choices are correct
Subelement E7
PRACTICAL CIRCUITS
Removed questions: 31
New questions: 22
Updated questions: 13
Total questions: 117
Section E7A
Digital circuits: digital circuit principles and logic circuits: classes of logic elements; positive and negative logic; frequency dividers; truth tables
Removed questions: 4
New questions: 1
Updated questions: 3
Total questions: 12
REMOVED
How many output level changes are obtained for every two trigger pulses applied to the input of a T flip-flop circuit?
None
One
Two
Four
REMOVED
What is an SR or RS flip-flop?
A speed-reduced logic device with high power capability
A set/reset flip-flop whose output is low when R is high and S is low, high when S is high and R is low, and unchanged when both inputs are low
A speed-reduced logic device with very low voltage operation capability
A set/reset flip-flop that toggles whenever the T input is pulsed, unless both inputs are high
REMOVED
What is a JK flip-flop?
A flip-flop similar to an RS except that it toggles when both J and K are high
A flip-flop utilizing low power, low temperature Joule-Kelvin devices
A flip-flop similar to a D flip-flop except that it triggers on the negative clock edge
A flip-flop originally developed in Japan and Korea which has very low power consumption
REMOVED
What is a D flip-flop?
A flip-flop whose output takes on the state of the D input when the clock signal transitions from low to high
A differential class D amplifier used as a flip-flop circuit
A dynamic memory storage element
A flip-flop whose output is capable of both positive and negative voltage excursions
Which of the following is a bistablebi-stable circuit?
An "AND" gate
An "OR" gate
A flip-flop
A clock
was E7F03
What is the function of a decade counter digital IC?
It produces one output pulse for every ten input pulses
It decodes a decimal number for display on a seven- segment LED display
It produces ten output pulses for every input pulse
It adds two decimal numbers together
Which of the following can divide the frequency of a pulse train by 2?
An XOR gate
A flip-flop
An OR gate
A multiplexer
How many flip-flops are required to divide a signal frequency by 4?
1
2
4
8
Which of the following is a circuit that continuously alternates between two states without an external clock?
Monostable multivibrator
J-K flip-flop
T flip-flop
Astable multivibrator
What is a characteristic of a monostable multivibrator?
It switches momentarily to the opposite binary state and then returns, to its original state after a set time, to its original state
It is a clock that It produces a continuous square wave oscillating between 1 and 0
It stores one bit of data in either a 0 or 1 state
It maintains a constant output voltage, regardless of variations in the input voltage
What logical operation does a NAND gate perform?
It produces a logic "0" at its output only when all inputs are logic "0"
It produces a logic "1" at its output only when all inputs are logic "1"
It produces a logic "0" at its output if some but not all of its inputs are logic "1"
It produces a logic "0" at its output only when all inputs are logic "1"
What logical operation does an OR gate perform?
It produces a logic "1" at its output if any or all inputs are logic "1"
It produces a logic "0" at its output if all inputs are logic "1"
It only produces a logic "0" at its output when all inputs are logic "1"
It produces a logic "1" at its output if all inputs are logic "0"
- NEW -
What logical operation is performed by an exclusive NOR gate?
It produces logic "0" at its output only if all inputs are logic "0"
It produces logic "1" at its output only if all inputs are logic "1"
It produces logic "0" at its output if any single input is logic "1"
It produces logic "1" at its output if any single input is logic "1"
What is a truth table?
A table of logic symbols that indicate the high logic states of an op-amp
A diagram showing logic states when the digital device's output is true
A list of inputs and corresponding outputs for a digital device
A table of logic symbols that indicatesindicate the low logic states of an op-amp
What is the name for type of logic which represents a logic defines "1" as a high voltage?
Reverse Logic
Assertive Logic
Negative logic
Positive Logic
What is the name for type of logic which represents a logic defines "0" as a high voltage?
Reverse Logic
Assertive Logic
Negative logic
Positive Logic
Section E7B
Amplifiers: Class of operation; vacuum tube and solid-state circuits; distortion and intermodulation; spurious and parasitic suppression; microwave amplifiers; switching-type amplifiers
Removed questions: 4
New questions: 1
Updated questions: 4
Total questions: 18
REMOVED
In Figure E7-2, what is the purpose of C2?
Output coupling
Emitter bypass
Input coupling
Hum filtering
REMOVED
What is a klystron?
A high speed multivibrator
An electron-coupled oscillator utilizing a pentode vacuum tube
An oscillator utilizing ceramic elements to achieve stability
A VHF, UHF, or microwave vacuum tube that uses velocity modulation
REMOVED
What is a parametric amplifier?
A type of bipolar operational amplifier with excellent linearity derived from use of very high voltage on the collector
A low-noise VHF or UHF amplifier relying on varying reactance for amplification
A high power amplifier for HF application utilizing the Miller effect to increase gain
An audio push-pull amplifier using silicon carbide transistors for extremely low noise
REMOVED
Which of the following devices is generally best suited for UHF or microwave power amplifier applications?
Field effect transistor
Nuvistor
Silicon controlled rectifier
Triac
For what portion of a signal cycle does a Class AB amplifier operate?
More than 180 degrees but less than 360 degrees
Exactly 180 degrees
The entire cycle
Less than 180 degrees
What is a Class D amplifier?
A type of amplifier that uses switching technology to achieve high efficiency
A low power amplifier using that uses a differential amplifier for improved linearity
An amplifier using that uses drift-mode FETs for high efficiency
A frequency doubling amplifier
Which of the following forms components form the output of a class D amplifier circuit?
A low-pass filter to remove switching signal components
A high-pass filter to compensate for low gain at low frequencies
A matched load resistor to prevent damage by switching transients
A temperature-compensated compensating load resistor to improve linearity
Where on the load line of a Class A common emitter amplifier would bias normally be set?
Approximately half-way between saturation and cutoff
Where the load line intersects the voltage axis
At a point where the bias resistor equals the load resistor
At a point where the load line intersects the zero bias current curve
What can be done to prevent unwanted oscillations in an RF power amplifier?
Tune the stage for maximum SWR
Tune both the input and output for maximum power
Install parasitic suppressors and/or neutralize the stage
Use a phase inverter in the output filter
Which of the following amplifier types reduces or eliminates even- order harmonics?
Push-push
Push-pull
Class C
Class AB
Which of the following is a likely result when a Class C amplifier is used to amplify a single-sideband phone signal?
Reduced intermodulation products
Increased overall intelligibility
Signal inversion
Signal distortion and excessive bandwidth
How can an RF power amplifier be neutralized?
By increasing the driving power
By reducing the driving power
By feeding a 180-degree out-of-phase portion of the output back to the input
By feeding an in-phase component of the output back to the input
Which of the following describes how the loading and tuning capacitors are to be adjusted when tuning a vacuum tube RF power amplifier that employs a piPi-network output circuit?
The loading capacitor is set to maximum capacitance and the tuning capacitor is adjusted for minimum allowable plate current
The tuning capacitor is set to maximum capacitance and the loading capacitor is adjusted for minimum plate permissible current
The loading capacitor is adjusted to minimum plate current while alternately adjusting the tuning capacitor for maximum allowable plate current
The tuning capacitor is adjusted for minimum plate current, whileand the loading capacitor is adjusted for maximum permissible plate current
In Figure E7-1, what is the purpose of R1 and R2?
Load resistors
Fixed bias
Self bias
Feedback
In Figure E7-1, what is the purpose of R3?
Fixed bias
Emitter bypass
Output load resistor
Self bias
What type of amplifier circuit is shown in Figure E7-1?
Switching voltage regulatorCommon base
Common collectorLinear voltage regulator
Common emitter amplifierCommon emitter
Emitter follower amplifier
In Figure E7-2, what is the purpose of R?
Emitter load
Fixed bias
Collector load
Voltage regulation
- NEW -
Why are switching amplifiers more efficient than linear amplifiers?
Switching amplifiers operate at higher voltages
The power transistor is at saturation or cut off most of the time, resulting in low power dissipation
Linear amplifiers have high gain resulting in higher harmonic content
Switching amplifiers use push-pull circuits
What is one way to prevent thermal runaway in a bipolar transistor amplifier?
Neutralization
Select transistors with high beta
Use a resistor in series with the emitter
All of these choices are correct
What is the effect of intermodulation products in a linear power amplifier?
Transmission of spurious signals
Creation of parasitic oscillations
Low efficiency
All of these choices are correct
Why are thirdodd-order rather than even-order intermodulation distortion products of particular concern in linear power amplifiers?
Because they are relatively close in frequency to the desired signal
Because they are relatively far in frequency from the desired signal
Because they invert the sidebands causing distortion
Because they maintain the sidebands, thus causing multiple duplicate signals
Which of the following What is a characteristic of a grounded-grid amplifier?
High power gain
High filament voltage
Low input impedance
Low bandwidth
Section E7C
Filters and matching networks: types of networks; types of filters; filter applications; filter characteristics; impedance matching; DSP filtering
Removed questions: 0
New questions: 0
Updated questions: 2
Total questions: 15
How are the capacitors and inductors of a low-pass filter Pi-network arranged between the network's input and output?
Two inductors are in series between the input and output, and a capacitor is connected between the two inductors and ground
Two capacitors are in series between the input and output, and an inductor is connected between the two capacitors and ground
An inductor is connected between the input and ground, another inductor is connected between the output and ground, and a capacitor is connected between the input and output
A capacitor is connected between the input and ground, another capacitor is connected between the output and ground, and an inductor is connected between input and output
A Which of the following is a property of a T-network with series capacitors and a parallel shunt inductor? has which of the following properties?
It is a low-pass filter
It is a band-pass filter
It is a high-pass filter
It is a notch filter
What advantage does a Pi-L-network have over a regular Pi-network for impedance matching between the final amplifier of a vacuum-tube transmitter and an antenna?
Greater harmonic suppression
Higher efficiency
Lower losses
Greater transformation range
How does an impedance-matching circuit transform a complex impedance to a resistive impedance?
It introduces negative resistance to cancel the resistive part of impedance
It introduces transconductance to cancel the reactive part of impedance
It cancels the reactive part of the impedance and changes the resistive part to a desired value
Network resistances are substituted for load resistances and reactances are matched to the resistances
Which filter type is described as having ripple in the passband and a sharp cutoff?
A Butterworth filter
An active LC filter
A passive op-amp filter
A Chebyshev filter
What are the distinguishing features of an elliptical filter?
Gradual passband rolloff with minimal stop band ripple
Extremely flat response over its pass band with gradually rounded stop band corners
Extremely sharp cutoff with one or more notches in the stop band
Gradual passband rolloff with extreme stop band ripple
What kind of filter would you use to attenuate an interfering carrier signal while receiving an SSB transmission?
A band-pass filter
A notch filter
A Pi-network filter
An all-pass filter
was E6E02
Which of the following factors has the greatest effect in helping determine the bandwidth and response shape of a crystal ladder filter?
The relative frequencies of the individual crystals
The DC voltage applied to the quartz crystal
The gain of the RF stage preceding the filter
The amplitude of the signals passing through the filter
was E6E12
What is a "Jones filter" as used as part of aan HF receiver IF stage?
An automatic notch filter
A variable bandwidth crystal lattice filter
A special filter that emphasizes image responses
A filter that removes impulse noise
Which of the following filters would be the best choice for use in a 2 meter repeater duplexer?
A crystal filter
A cavity filter
A DSP filter
An L-C filter
Which of the following is the common name for a filter network which is equivalent to two L-networks connected back-to-back with the two inductors in series and the capacitors in shunt at the input and output?
Pi-L
Cascode
Omega
Pi
Which of the following describes a Pi-L-network used for matching a vacuum- tube final amplifier to a 50- ohm unbalanced output?
A Phase Inverter Load network
A Pi A Pi-network with an additional series inductor on the output
A network with only three discrete parts
A matching network in which all components are isolated from ground
What is one advantage of a Pi-matching network over an L-matching network consisting of a single inductor and a single capacitor?
The Q of Pi-networks can be varied depending on the component values chosen
L L-networks cannot perform impedance transformation
Pi Pi-networks have fewer components
Pi Pi-networks are designed for balanced input and output
Which of these modes mode is most affected by non-linear phase response in a receiver IF filter?
Meteor ScatterMeteor scatter
Single-Sideband voice
Digital
Video
was E6E01
What is a crystal lattice filter?
A power supply filter made with interlaced quartz crystals
An audio filter made with four quartz crystals that resonate at 1-kHz1kHz intervals
A filter with wide bandwidth and shallow skirts made using quartz crystals
A filter with narrow bandwidth and steep skirts made using quartz crystals
Section E7D
Power supplies and voltage regulators; Solar array charge controllers
Removed questions: 5
New questions: 4
Updated questions: 0
Total questions: 16
REMOVED
What is the purpose of C1 in the circuit shown in Figure E7-3?
It resonates at the ripple frequency
It provides fixed bias for Q1
It decouples the output
It filters the supply voltage
REMOVED
What is the purpose of C3 in the circuit shown in Figure E7-3?
It prevents self-oscillation
It provides brute force filtering of the output
It provides fixed bias for Q1
It clips the peaks of the ripple
REMOVED
What is the purpose of R1 in the circuit shown in Figure E7-3?
It provides a constant load to the voltage source
It couples hum to D1
It supplies current to D1
It bypasses hum around D1
REMOVED
What is the purpose of R2 in the circuit shown in Figure E7-3?
It provides fixed bias for Q1
It provides fixed bias for D1
It decouples hum from D1
It provides a constant minimum load for Q1
REMOVED
What is the purpose of D1 in the circuit shown in Figure E7-3?
To provide line voltage stabilization
To provide a voltage reference
Peak clipping
Hum filtering
What is one characteristic of a linear electronic voltage regulator?
It has a ramp voltage as its output
It eliminates the need for a pass transistor
The control element duty cycle is proportional to the line or load conditions
The conduction of a control element is varied to maintain a constant output voltage
What is one characteristic of a switching electronic voltage regulator?
The resistance of a control element is varied in direct proportion to the line voltage or load current
It is generally less efficient than a linear regulator
The controlThe controlled device's duty cycle is controlledchanged to produce a constant average output voltage
It gives a ramp voltage at its output
What device is typically used as a stable reference voltage in a linear voltage regulator?
A Zener diode
A tunnel diode
An SCR
A varactor diode
Which of the following types of linear voltage regulator usually make the most efficient use of the primary power source?
A series current source
A series regulator
A shunt regulator
A shunt current source
Which of the following types of linear voltage regulator places a constant load on the unregulated voltage source?
A constant current source
A series regulator
A shunt current source
A shunt regulator
What is the purpose of Q1 in the circuit shown in Figure E7-3?
It provides negative feedback to improve regulation
It provides a constant load for the voltage source
It increases the current-handling capability of the regulator
It provides D1 with current
What is the purpose of C2 in the circuit shown in Figure E7-3?
It bypasses hum around D1
It is a brute force filter for the output
To self-resonate at the hum frequency
To provide fixed DC bias for Q1
What type of circuit is shown in Figure E7-3?
Switching voltage regulator
Grounded emitter amplifier
Linear voltage regulator
Emitter follower
- NEW -
What is the main reason to use a charge controller with a solar power system?
Prevention of battery undercharge
Control of electrolyte levels during battery discharge
Prevention of battery damage due to overcharge
Matching of day and night charge rates
was E7D17
What is the primary reason that a high-frequency inverterswitching type high- voltage power supply can be both less expensive and lighter in weight than a conventional power supply?
The inverter design does not require any output filtering
It uses a diode bridge rectifier for increased output
The high frequency inverter design uses much smaller transformers and filter components for an equivalent power output
It uses a large power- factor compensation capacitor to create "free power" from the unused portion of the AC cycle
- NEW -
What circuit element is controlled by a series analog voltage regulator to maintain a constant output voltage?
Reference voltage
Switching inductance
Error amplifier
Pass transistor
- NEW -
What is the drop-out voltage of an analog voltage regulator?
Minimum input voltage for rated power dissipation
Maximum amount that the output voltage drops when the input voltage is varied over its specified range
Minimum input-to-output voltage required to maintain regulation
Maximum amount that the output voltage may decrease at rated load
- NEW -
What is the equation for calculating power dissipation by a series connected linear voltage regulator?
Input voltage multiplied by input current
Input voltage divided by output current
Voltage difference from input to output multiplied by output current
Output voltage multiplied by output current
What is one purpose of a "bleeder" resistor in a conventional (unregulated) power supply?
To cut down on waste heat generated by the power supply
To balance the low-voltage filament windings
To improve output voltage regulation
To boost the amount of output current
What is the purpose of a "step-start" circuit in a high- voltage power supply?
To provide a dual-voltage output for reduced power applications
To compensate for variations of the incoming line voltage
To allow for remote control of the power supply
To allow the filter capacitors to charge gradually
When several electrolytic filter capacitors are connected in series to increase the operating voltage of a power supply filter circuit, why should resistors be connected across each capacitor?
To equalize, as much as possible, the voltage drop across each capacitor
To provide a safety bleeder to discharge the capacitors when the supply is off
To provide a minimum load current to reduce voltage excursions at light loads
All of these choices are correct
Section E7E
Modulation and demodulation: reactance, phase and balanced modulators; detectors; mixer stages; DSP modulation and demodulation; software defined radio systems
Removed questions: 0
New questions: 0
Updated questions: 1
Total questions: 12
Which of the following can be used to generate FM phone emissions?
A balanced modulator on the audio amplifier
A reactance modulator on the oscillator
A reactance modulator on the final amplifier
A balanced modulator on the oscillator
What is the function of a reactance modulator?
To produce PM signals by using an electrically variable resistance
To produce AM signals by using an electrically variable inductance or capacitance
To produce AM signals by using an electrically variable resistance
To produce PM signals by using an electrically variable inductance or capacitance
How does an analog phase modulator function?
By varying the tuning of a microphone preamplifier to produce PM signals
By varying the tuning of an amplifier tank circuit to produce AM signals
By varying the tuning of an amplifier tank circuit to produce PM signals
By varying the tuning of a microphone preamplifier to produce AM signals
What is one way a single-sideband phone signal can be generated?
By using a balanced modulator followed by a filter
By using a reactance modulator followed by a mixer
By using a loop modulator followed by a mixer
By driving a product detector with a DSB signal
What circuit is added to an FM transmitter to boost the higher audio frequencies?
A de-emphasis network
A heterodyne suppressor
An audio prescaler
A pre-emphasis network
Why is de-emphasis commonly used in FM communications receivers?
For compatibility with transmitters using phase modulation
To reduce impulse noise reception
For higher efficiency
To remove third-order distortion products
What is meant by the term baseband in radio communications?
The lowest frequency band that the transmitter or receiver covers
The frequency components present in the modulating signal
The unmodulated bandwidth of the transmitted signal
The basic oscillator frequency in an FM transmitter that is multiplied to increase the deviation and carrier frequency
What are the principal frequencies that appear at the output of a mixer circuit?
Two and four times the original frequency
The sum, difference and square root of the input frequencies
The two input frequencies along with their sum and difference frequencies
1.414 and 0.707 times the input frequency
What occurs when an excessive amount of signal energy reaches a mixer circuit?
Spurious mixer products are generated
Mixer blanking occurs
Automatic limiting occurs
A beat frequency is generated
How does a diode detector function?
By rectification and filtering of RF signals
By breakdown of the Zener voltage
By mixing signals with noise in the transition region of the diode
By sensing the change of reactance in the diode with respect to frequency
Which of the following types type of detector is well suited used for demodulating SSB signals?
Discriminator
Phase detector
Product detector
Phase comparator
What is a frequency discriminator stage in a FM receiver?
An FM generator circuit
A circuit for filtering two closely adjacent signals
An automatic band-switching circuit
A circuit for detecting FM signals
Section E7F
Frequency markersDSP filtering and other operations; Software Defined Radio Fundamentals; DSP modulation and demodulationcounters: frequency divider circuits; frequency marker generators; frequency counters
Removed questions: 7
New questions: 13
Updated questions: 2
Total questions: 17
REMOVED
Which of the following would be used to reduce a signal's frequency by a factor of ten?
A preamp
A prescaler
A marker generator
A flip-flop
REMOVED
What additional circuitry must be added to a 100-kHz crystal-controlled marker generator so as to provide markers at 50 and 25 kHz?
An emitter-follower
Two frequency multipliers
Two flip-flops
A voltage divider
REMOVED
What is one purpose of a marker generator?
To add audio markers to an oscilloscope
To provide a frequency reference for a phase locked loop
To provide a means of calibrating a receiver's frequency settings
To add time signals to a transmitted signal
REMOVED
What determines the accuracy of a frequency counter?
The accuracy of the time base
The speed of the logic devices used
Accuracy of the AC input frequency to the power supply
Proper balancing of the mixer diodes
REMOVED
Which of the following is performed by a frequency counter?
Determining the frequency deviation with an FM discriminator
Mixing the incoming signal with a WWV reference
Counting the number of input pulses occurring within a specific period of time
Converting the phase of the measured signal to a voltage which is proportional to the frequency
REMOVED
What is the purpose of a frequency counter?
To provide a digital representation of the frequency of a signal
To generate a series of reference signals at known frequency intervals
To display all frequency components of a transmitted signal
To provide a signal source at a very accurate frequency
REMOVED
What alternate method of determining frequency, other than by directly counting input pulses, is used by some counters?
GPS averaging
Period measurement plus mathematical computation
Prescaling
D/A conversion
was E7E14
What is meant by direct digital conversion when referring to a as applied to software defined radios?receiver?
Software is converted from source code to object code during operation of the receiver
Incoming RF is converted to the IF frequency by rectification to generate the a control voltage for a voltage controlled oscillator
Incoming RF is mixed to "baseband" for digitized by an analog-to-digital converter without being mixed with a local oscillator signalconversion and subsequent processing
A switching mixer is used to generate I and Q signals directly from the RF inputSoftware is generated in machine language, avoiding the need for compilers
was E7C08
What kind of digital signal processing audio filter might be is used to remove unwanted noise from a received SSB signal?
An adaptive filter
A crystal-lattice filter
A Hilbert-transform filter
A phase-inverting filter
was E7C09
What type of digital signal processing filter might be is used to generate an SSB signal?
An adaptive filter
A notch filter
A Hilbert-transform filter
An elliptical filter
was E7E13
Which of the following describes What is a common meansmethod of generating an SSB signal when using digital signal processing?
Mixing products are converted to voltages and subtracted by adder circuits
A frequency synthesizer removes the unwanted sidebands
Emulation of quartz crystal filter characteristics
The Combine signals with a quadrature phase relationshipmethod
- NEW -
How frequently must an analog signal be sampled by an analog-to-digital converter so that the signal can be accurately reproduced?
At half the rate of the highest frequency component of the signal
At twice the rate of the highest frequency component of the signal
At the same rate as the highest frequency component of the signal
At four times the rate of the highest frequency component of the signal
- NEW -
What is the minimum number of bits required for an analog-to-digital converter to sample a signal with a range of 1 volt at a resolution of 1 millivolt?
4 bits
6 bits
8 bits
10 bits
- NEW -
What function can a Fast Fourier Transform perform?
Converting analog signals to digital form
Converting digital signals to analog form
Converting digital signals from the time domain to the frequency domain
Converting 8-bit data to 16 bit data
- NEW -
What is the function of decimation with regard to digital filters?
Converting data to binary code decimal form
Reducing the effective sample rate by removing samples
Attenuating the signal
Removing unnecessary significant digits
- NEW -
Why is an anti-aliasing digital filter required in a digital decimator?
It removes high-frequency signal components which would otherwise be reproduced as lower frequency components
It peaks the response of the decimator, improving bandwidth
It removes low frequency signal components to eliminate the need for DC restoration
It notches out the sampling frequency to avoid sampling errors
- NEW -
What aspect of receiver analog-to-digital conversion determines the maximum receive bandwidth of a Direct Digital Conversion SDR?
Sample rate
Sample width in bits
Sample clock phase noise
Processor latency
- NEW -
What sets the minimum detectable signal level for an SDR in the absence of atmospheric or thermal noise?
Sample clock phase noise
Reference voltage level and sample width in bits
Data storage transfer rate
Missing codes and jitter
- NEW -
What digital process is applied to I and Q signals in order to recover the baseband modulation information?
Fast Fourier Transform
Decimation
Signal conditioning
Quadrature mixing
- NEW -
What is the function of taps in a digital signal processing filter?
To reduce excess signal pressure levels
Provide access for debugging software
Select the point at which baseband signals are generated
Provide incremental signal delays for filter algorithms
- NEW -
Which of the following would allow a digital signal processing filter to create a sharper filter response?
Higher data rate
More taps
Complex phasor representations
Double-precision math routines
- NEW -
Which of the following is an advantage of a Finite Impulse Response (FIR) filter vs an Infinite Impulse Response (IIR) digital filter?
FIR filters delay all frequency components of the signal by the same amount
FIR filters are easier to implement for a given set of passband rolloff requirements
FIR filters can respond faster to impulses
All of these choices are correct
- NEW -
How might the sampling rate of an existing digital signal be adjusted by a factor of 3/4?
Change the gain by a factor of 3/4
Multiply each sample value by a factor of 3/4
Add 3 to each input value and subtract 4 from each output value
Interpolate by a factor of three, then decimate by a factor of four
- NEW -
What do the letters I and Q in I/Q Modulation represent?
Inactive and Quiescent
Instantaneous and Quasi-stable
Instantaneous and Quenched
In-phase and Quadrature
Section E7G
Active filters and op-ampsamp circuits: active audio filters; characteristics; basic circuit design; operational amplifiers
Removed questions: 3
New questions: 0
Updated questions: 0
Total questions: 12
REMOVED
What primarily determines the gain and frequency characteristics of an op-amp RC active filter?
The values of capacitors and resistors built into the op-amp
The values of capacitors and resistors external to the op-amp
The input voltage and frequency of the op-amp's DC power supply
The output voltage and smoothness of the op-amp's DC power supply
REMOVED
Which of the following is an advantage of using an op-amp instead of LC elements in an audio filter?
Op-amps are more rugged
Op-amps are fixed at one frequency
Op-amps are available in more varieties than are LC elements
Op-amps exhibit gain rather than insertion loss
REMOVED
Which of the following is a type of capacitor best suited for use in high-stability op-amp RC active filter circuits?
Electrolytic
Disc ceramic
Polystyrene
Paper
was E7G15
What is the typical output impedance of an integrated circuit op-amp?
Very low
Very high
100 ohms
1000 ohms
What is the effect of ringing in a filter?
An echo caused by a long time delay
A reduction in high frequency response
Partial cancellation of the signal over a range of frequencies
Undesired oscillations added to the desired signal
was E7G14
What is the typical input impedance of an integrated circuit op-amp?
100 ohms
1000 ohms
Very low
Very high
was E7G13
What is meant by the term op-amp input- offset voltage?
The output voltage of the op-amp minus its input voltage
The difference between the output voltage of the op-amp and the input voltage required in the immediately following stage
The differential input voltage needed to bring the open- loop output voltage to zero
The potential between the amplifier input terminals of the op-amp in an open- loop condition
How can unwanted ringing and audio instability be prevented in a multi-section op-amp RC audio filter circuit?
Restrict both gain and Q
Restrict gain, but increase Q
Restrict Q, but increase gain
Increase both gain and Q
Which of the following is the most appropriate use of an op-amp active filter?
As a high-pass filter used to block RFI at the input to receivers
As a low-pass filter used between a transmitter and a transmission line
For smoothing power- supply output
As an audio filter in a receiver
What magnitude of voltage gain can be expected from the circuit in Figure E7-4 when R1 is 10 ohms and RF is 470 ohms?
0.21
94
47
24
How does the gain of an ideal operational amplifier vary with frequency?
It increases linearly with increasing frequency
It decreases linearly with increasing frequency
It decreases logarithmically with increasing frequency
It does not vary with frequency
What will be the output voltage of the circuit shown in Figure E7-4 if R1 is 1000 ohms, RF is 10,000 ohms, and 0.23 volts dcDC is applied to the input?
0.23 volts
2.3 volts
-0.23 volts
-2.3 volts
What absolute voltage gain can be expected from the circuit in Figure E7-4 when R1 is 1800 ohms and RF is 68 kilohms?
1
0.03
38
76
What absolute voltage gain can be expected from the circuit in Figure E7-4 when R1 is 3300 ohms and RF is 47 kilohms?
28
14
7
0.07
What is an integrated circuit operational amplifier?
A high-gain, direct-coupled differential amplifier with very high input impedance and very low output impedance
A digital audio amplifier whose characteristics are determined by components external to the amplifier
An amplifier used to increase the average output of frequency modulated amateur signals to the legal limit
AnA RF amplifier used in the UHF and microwave regions
Section E7H
Oscillators and signal sources: types of oscillators; synthesizers and phase-locked loops; direct digital synthesizers; stabilizing thermal drift; microphonics; high accuracy oscillators
Removed questions: 8
New questions: 3
Updated questions: 1
Total questions: 15
REMOVED
What condition must exist for a circuit to oscillate?
It must have at least two stages
It must be neutralized
It must have positive feedback with a gain greater than 1
It must have negative feedback sufficient to cancel the input signal
REMOVED
What is a magnetron oscillator?
An oscillator in which the output is fed back to the input by the magnetic field of a transformer
A crystal oscillator in which variable frequency is obtained by placing the crystal in a strong magnetic field
A UHF or microwave oscillator consisting of a diode vacuum tube with a specially shaped anode, surrounded by an external magnet
A reference standard oscillator in which the oscillations are synchronized by magnetic coupling to a rubidium gas tube
REMOVED
What is a Gunn diode oscillator?
An oscillator based on the negative resistance properties of properly-doped semiconductors
An oscillator based on the argon gas diode
A highly stable reference oscillator based on the tee-notch principle
A highly stable reference oscillator based on the hot-carrier effect
REMOVED
Which of the following is a principal component of a direct digital synthesizer (DDS)?
Phase splitter
Hex inverter
Chroma demodulator
Phase accumulator
REMOVED
What is the capture range of a phase-locked loop circuit?
The frequency range over which the circuit can lock
The voltage range over which the circuit can lock
The input impedance range over which the circuit can lock
The range of time it takes the circuit to lock
REMOVED
Why is the short-term stability of the reference oscillator important in the design of a phase locked loop (PLL) frequency synthesizer?
Any amplitude variations in the reference oscillator signal will prevent the loop from locking to the desired signal
Any phase variations in the reference oscillator signal will produce phase noise in the synthesizer output
Any phase variations in the reference oscillator signal will produce harmonic distortion in the modulating signal
Any amplitude variations in the reference oscillator signal will prevent the loop from changing frequency
REMOVED
Why is a phase-locked loop often used as part of a variable frequency synthesizer for receivers and transmitters?
It generates FM sidebands
It eliminates the need for a voltage controlled oscillator
It makes it possible for a VFO to have the same degree of frequency stability as a crystal oscillator
It can be used to generate or demodulate SSB signals by quadrature phase synchronization
REMOVED
What are the major spectral impurity components of phase-locked loop synthesizers?
Phase noise
Digital conversion noise
Spurious signals at discrete frequencies
Nyquist limit noise
What are three oscillator circuits used in Amateur Radio equipment?
Taft, Pierce and negative feedback
Pierce, Fenner and Beane
Taft, Hartley and Pierce
Colpitts, Hartley and Pierce
- NEW -
Which describes a microphonic?
An IC used for amplifying microphone signals
Distortion caused by RF pickup on the microphone cable
Changes in oscillator frequency due to mechanical vibration
Excess loading of the microphone by an oscillator
How is positive feedback supplied in a Hartley oscillator?
Through a tapped coil
Through a capacitive divider
Through link coupling
Through a neutralizing capacitor
How is positive feedback supplied in a Colpitts oscillator?
Through a tapped coil
Through link coupling
Through a capacitive divider
Through a neutralizing capacitor
How is positive feedback supplied in a Pierce oscillator?
Through a tapped coil
Through link coupling
Through a neutralizing capacitor
Through a quartz crystal
Which of the following oscillator circuits are commonly used in VFOs?
Pierce and Zener
Colpitts and Hartley
Armstrong and deForest
Negative feedback and balanced feedback
- NEW -
How can an oscillator's microphonic responses be reduced?
Use of NP0 capacitors
Eliminating noise on the oscillator's power supply
Using the oscillator only for CW and digital signals
Mechanically isolating the oscillator circuitry from its enclosure
- NEW -
Which of the following components can be used to reduce thermal drift in crystal oscillators?
NP0 capacitors
Toroidal inductors
Wirewound resistors
Non-inductive resistors
What type of frequency synthesizer circuit uses a phase accumulator, lookup table, digital to analog converter, and a low-pass anti-alias filter?
A direct digital synthesizer
A hybrid synthesizer
A phase locked loop synthesizer
A diode-switching matrix synthesizer
What information is contained in the lookup table of a direct digital frequency synthesizer?
The phase relationship between a reference oscillator and the output waveform
The amplitude values that represent a sine-wave output
The phase relationship between a voltage-controlled oscillator and the output waveform
The synthesizer frequency limits and frequency values stored in the radio memories
What are the major spectral impurity components of direct digital synthesizers?
Broadband noise
Digital conversion noise
Spurious signals at discrete frequencies
Nyquist limit noise
was E6E09
Which of the following must be done to insure that a crystal oscillator provides the frequency specified by the crystal manufacturer?
Provide the crystal with a specified parallel inductance
Provide the crystal with a specified parallel capacitance
Bias the crystal at a specified voltage
Bias the crystal at a specified current
was E7F05
Which of the following is a technique for providing high stability highly accurate and stable oscillators needed for microwave transmission and reception?
Use a GPS signal reference
Use a rubidium stabilized reference oscillator
Use a temperature-controlled high Q dielectric resonator
All of these choices are correct
What is a phase-locked loop circuit?
An electronic servo loop consisting of a ratio detector, reactance modulator, and voltage-controlled oscillator
An electronic circuit also known as a monostable multivibrator
An electronic servo loop consisting of a phase detector, a low-pass filter, a voltage-controlled oscillator, and a stable reference oscillator
An electronic circuit consisting of a precision push-pull amplifier with a differential input
Which of these functions can be performed by a phase-locked loop?
Wide-band AF and RF power amplification
Comparison of two digital input signals, digital pulse counter
Photovoltaic conversion, optical coupling
Frequency synthesis, FM demodulation
Subelement E8
SIGNALS AND EMISSIONS
Removed questions: 27
New questions: 18
Updated questions: 2
Total questions: 47
Section E8A
AC waveforms: sine, square, sawtooth and irregular waveforms; AC measurements; average and PEP of RF signals; pulse and Fourier analysis; Analog to digital conversion: Digital to Analog conversionsignal waveforms
Removed questions: 7
New questions: 5
Updated questions: 1
Total questions: 13
REMOVED
What type of wave is made up of a sine wave plus all of its odd harmonics?
A square wave
A sine wave
A cosine wave
A tangent wave
REMOVED
What is equivalent to the root-mean-square value of an AC voltage?
The AC voltage found by taking the square of the average value of the peak AC voltage
The DC voltage causing the same amount of heating in a given resistor as the corresponding peak AC voltage
The DC voltage causing the same amount of heating in a resistor as the corresponding RMS AC voltage
The AC voltage found by taking the square root of the average AC value
REMOVED
What is the period of a wave?
The time required to complete one cycle
The number of degrees in one cycle
The number of zero crossings in one cycle
The amplitude of the wave
REMOVED
What type of waveform is produced by human speech?
Sinusoidal
Logarithmic
Irregular
Trapezoidal
REMOVED
Which of the following is a distinguishing characteristic of a pulse waveform?
Regular sinusoidal oscillations
Narrow bursts of energy separated by periods of no signal
A series of tones that vary between two frequencies
A signal that contains three or more discrete tones
REMOVED
What is one use for a pulse modulated signal?
Linear amplification
PSK31 data transmission
Multiphase power transmission
Digital data transmission
REMOVED
What would the waveform of a stream of digital data bits look like on a conventional oscilloscope?
A series of sine waves with evenly spaced gaps
A series of pulses with varying patterns
A running display of alpha-numeric characters
None of the above; this type of signal cannot be seen on a conventional oscilloscope
- NEW -
What is the name of the process that shows that a square wave is made up of a sine wave plus all of its odd harmonics?
Fourier analysis
Vector analysis
Numerical analysis
Differential analysis
What type of wave has a rise time significantly faster than its fall time (or vice versa)?
A cosine wave
A square wave
A sawtooth wave
A sine wave
What type of wave is does a Fourier analysis show to be made up of sine waves of a given fundamental frequency plus all of its harmonics?
A sawtooth wave
A square wave
A sine wave
A cosine wave
- NEW -
What is "dither" with respect to analog to digital converters?
An abnormal condition where the converter cannot settle on a value to represent the signal
A small amount of noise added to the input signal to allow more precise representation of a signal over time
An error caused by irregular quantization step size
A method of decimation by randomly skipping samples
What would be the most accurate way of measuring the RMS voltage of a complex waveform?
By using a grid dip meter
By measuring the voltage with a D'Arsonval meter
By using an absorption wave meterwavemeter
By measuring the heating effect in a known resistor
What is the approximate ratio of PEP-to-average power in a typical single-sideband phone signal?
2.5 to 1
25 to 1
1 to 1
100 to 1
What determines the PEP-to-average power ratio of a single-sideband phone signal?
The frequency of the modulating signal
The characteristics of the modulating signal
The degree of carrier suppression
The amplifier gain
- NEW -
Why would a direct or flash conversion analog-to-digital converter be useful for a software defined radio?
Very low power consumption decreases frequency drift
Immunity to out of sequence coding reduces spurious responses
Very high speed allows digitizing high frequencies
All of these choices are correct
- NEW -
How many levels can an analog-to-digital converter with 8 bit resolution encode?
8
8 multiplied by the gain of the input amplifier
256 divided by the gain of the input amplifier
256
- NEW -
What is the purpose of a low pass filter used in conjunction with a digital-to-analog converter?
Lower the input bandwidth to increase the effective resolution
Improve accuracy by removing out of sequence codes from the input
Remove harmonics from the output caused by the discrete analog levels generated
All of these choices are correct
was E8A12
What type of information can be conveyed using digital waveforms?
Human speech
Video signals
Data
All of these choices are correct
was E8A13
What is an advantage of using digital signals instead of analog signals to convey the same information?
Less complex circuitry is required for digital signal generation and detection
Digital signals always occupy a narrower bandwidth
Digital signals can be regenerated multiple times without error
All of these choices are correct
was E8A14
Which of these methods is commonly used to convert analog signals to digital signals?
Sequential sampling
Harmonic regeneration
Level shifting
Phase reversal
Section E8B
Modulation and demodulation: modulation methods; modulation index and deviation ratio; pulse modulation; frequency and time division multiplexing; Orthogonal Frequency Division Multiplexing
Removed questions: 3
New questions: 2
Updated questions: 1
Total questions: 11
REMOVED
When using a pulse-width modulation system, why is the transmitter's peak power greater than its average power?
The signal duty cycle is less than 100%
The signal reaches peak amplitude only when voice modulated
The signal reaches peak amplitude only when voltage spikes are generated within the modulator
The signal reaches peak amplitude only when the pulses are also amplitude modulated
REMOVED
What parameter does the modulating signal vary in a pulse-position modulation system?
The number of pulses per second
The amplitude of the pulses
The duration of the pulses
The time at which each pulse occurs
REMOVED
Which of these methods can be used to combine several separate analog information streams into a single analog radio frequency signal?
Frequency shift keying
A diversity combiner
Frequency division multiplexing
Pulse compression
What is the term for the ratio between the frequency deviation of an RF carrier wave, and the modulating frequency of its corresponding FM-phone signal?
FM compressibility
Quieting index
Percentage of modulation
Modulation index
How does the modulation index of a phase-modulated emission vary with RF carrier frequency (the modulated frequency)?
It increases as the RF carrier frequency increases
It decreases as the RF carrier frequency increases
It varies with the square root of the RF carrier frequency
It does not depend on the RF carrier frequency
What is the modulation index of an FM-phone signal having a maximum frequency deviation of 3000 Hz either side of the carrier frequency, when the modulating frequency is 1000 Hz?
3
0.3
3000
1000
What is the modulation index of an FM-phone signal having a maximum carrier deviation of plus or minus 6 kHz when modulated with a 2- kHz modulating frequency?
6000
3
2000
1/3
What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus-or-minus 5 kHz when the maximum modulation frequency is 3 kHz?
60
0.167
0.6
1.67
What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus or minus 7.5 kHz when the maximum modulation frequency is 3.5 kHz?
2.14
0.214
0.47
47
- NEW -
Orthogonal Frequency Division Multiplexing is a technique used for which type of amateur communication?
High speed digital modes
Extremely low-power contacts
EME
OFDM signals are not allowed on amateur bands
- NEW -
What describes Orthogonal Frequency Division Multiplexing?
A frequency modulation technique which uses non-harmonically related frequencies
A bandwidth compression technique using Fourier transforms
A digital mode for narrow band, slow speed transmissions
A digital modulation technique using subcarriers at frequencies chosen to avoid intersymbol interference
What is meant by deviation ratio?
The ratio of the audio modulating frequency to the center carrier frequency
The ratio of the maximum carrier frequency deviation to the highest audio modulating frequency
The ratio of the carrier center frequency to the audio modulating frequency
The ratio of the highest audio modulating frequency to the average audio modulating frequency
was E8B11
Which of the following What describes frequency division multiplexing?
The transmitted signal jumps from band to band at a predetermined rate
Two or more information streams are merged into a "baseband", which then modulates the transmitter
The transmitted signal is divided into packets of information
Two or more information streams are merged into a digital combiner, which then pulse position modulates the transmitter
was E8B12
What is digital time division multiplexing?
Two or more data streams are assigned to discrete sub-carriers on an FM transmitter
Two or more signals are arranged to share discrete time slots of a data transmission
Two or more data streams share the same channel by transmitting time of transmission as the sub-carrier
Two or more signals are quadrature modulated to increase bandwidth efficiency
Section E8C
Digital signals: digital communicationscommunication modes; CW; information rate vs. bandwidth; error correctionspread-spectrum communications; modulation methods
Removed questions: 4
New questions: 5
Updated questions: 0
Total questions: 11
REMOVED
Which one of the following digital codes consists of elements having unequal length?
ASCII
AX.25
Baudot
Morse code
REMOVED
What term describes a wide-bandwidth communications system in which the transmitted carrier frequency varies according to some predetermined sequence?
Amplitude compandored single sideband
AMTOR
Time-domain frequency modulation
Spread-spectrum communication
REMOVED
Which of these techniques causes a digital signal to appear as wide-band noise to a conventional receiver?
Spread-spectrum
Independent sideband
Regenerative detection
Exponential addition
REMOVED
What spread-spectrum communications technique alters the center frequency of a conventional carrier many times per second in accordance with a pseudo-random list of channels?
Frequency hopping
Direct sequence
Time-domain frequency modulation
Frequency compandored spread-spectrum
was E2E03
How is Forward Error Correction implemented?
By the receiving station repeating each block of three data characters
By transmitting a special algorithm to the receiving station along with the data characters
By transmitting extra data that may be used to detect and correct transmission errors
By varying the frequency shift of the transmitted signal according to a predefined algorithm
- NEW -
What is the definition of symbol rate in a digital transmission?
The number of control characters in a message packet
The duration of each bit in a message sent over the air
The rate at which the waveform of a transmitted signal changes to convey information
The number of characters carried per second by the station-to-station link
- NEW -
When performing phase shift keying, why is it advantageous to shift phase precisely at the zero crossing of the RF carrier?
This results in the least possible transmitted bandwidth for the particular mode
It is easier to demodulate with a conventional, non-synchronous detector
It improves carrier suppression
All of these choices are correct
What technique is used to minimize the bandwidth requirements of a PSK31 signal?
Zero-sum character encoding
Reed-Solomon character encoding
Use of sinusoidal data pulses
Use of trapezoidal data pulses
What is the necessary bandwidth of a 13-WPM international Morse code transmission?
Approximately 13 Hz
Approximately 26 Hz
Approximately 52 Hz
Approximately 104 Hz
What is the necessary bandwidth of a 170-hertz shift, 300-baud ASCII transmission?
0.1 Hz
0.3 kHz
0.5 kHz
1.0 kHz
What is the necessary bandwidth of a 4800-Hz frequency shift, 9600-baud ASCII FM transmission?
15.36 kHz
9.6 kHz
4.8 kHz
5.76 kHz
was E2E05
How does ARQ accomplish error correction?
Special binary codes provide automatic correction
Special polynomial codes provide automatic correction
If errors are detected, redundant data is substituted
If errors are detected, a retransmission is requested
- NEW -
Which is the name of a digital code where each preceding or following character changes by only one bit?
Binary Coded Decimal Code
Extended Binary Coded Decimal Interchange Code
Excess 3 code
Gray code
- NEW -
What is an advantage of Gray code in digital communications where symbols are transmitted as multiple bits
It increases security
It has more possible states than simple binary
It has more resolution than simple binary
It facilitates error detection
- NEW -
What is the relationship between symbol rate and baud?
They are the same
Baud is twice the symbol rate
Symbol rate is only used for packet-based modes
Baud is only used for RTTY
Section E8D
Keying defects and overmodulation of digital signals; digital codes; spread spectrumWaveforms: measurement, peak-to-peak, RMS, average; Electromagnetic Waves: definition, characteristics, polarization
Removed questions: 13
New questions: 6
Updated questions: 0
Total questions: 12
REMOVED
Which of the following is the easiest voltage amplitude parameter to measure when viewing a pure sine wave signal on an analog oscilloscope?
Peak-to-peak voltage
RMS voltage
Average voltage
DC voltage
REMOVED
What is the relationship between the peak-to-peak voltage and the peak voltage amplitude of a symmetrical waveform?
0.707:1
2:1
1.414:1
4:1
REMOVED
What input-amplitude parameter is valuable in evaluating the signal-handling capability of a Class A amplifier?
Peak voltage
RMS voltage
Average power
Resting voltage
REMOVED
What is the PEP output of a transmitter that develops a peak voltage of 30 volts into a 50-ohm load?
4.5 watts
9 watts
16 watts
18 watts
REMOVED
If an RMS-reading AC voltmeter reads 65 volts on a sinusoidal waveform, what is the peak-to-peak voltage?
46 volts
92 volts
130 volts
184 volts
REMOVED
What is the advantage of using a peak-reading wattmeter to monitor the output of a SSB phone transmitter?
It is easier to determine the correct tuning of the output circuit
It gives a more accurate display of the PEP output when modulation is present
It makes it easier to detect high SWR on the feed line
It can determine if any flat-topping is present during modulation peaks
REMOVED
What type of meter should be used to monitor the output signal of a voice-modulated single-sideband transmitter to ensure you do not exceed the maximum allowable power?
An SWR meter reading in the forward direction
A modulation meter
An average reading wattmeter
A peak-reading wattmeter
REMOVED
What is the average power dissipated by a 50-ohm resistive load during one complete RF cycle having a peak voltage of 35 volts?
12.2 watts
9.9 watts
24.5 watts
16 watts
REMOVED
What is the peak voltage of a sinusoidal waveform if an RMS-reading voltmeter reads 34 volts?
123 volts
96 volts
55 volts
48 volts
REMOVED
Which of the following is a typical value for the peak voltage at a standard U.S. household electrical outlet?
240 volts
170 volts
120 volts
340 volts
REMOVED
Which of the following is a typical value for the peak-to-peak voltage at a standard U.S. household electrical outlet?
240 volts
120 volts
340 volts
170 volts
REMOVED
Which of the following is a typical value for the RMS voltage at a standard U.S. household electrical power outlet?
120V AC
340V AC
85V AC
170V AC
REMOVED
What is the RMS value of a 340-volt peak-to-peak pure sine wave?
120V AC
170V AC
240V AC
300V AC
was E2C08
Why are received spread- spectrum signals resistant to interference?
Signals not using the spread spectrum-spreading algorithm are suppressed in the receiver
The high power used by a spread- spectrum transmitter keeps its signal from being easily overpowered
The receiver is always equipped with a digital blanker circuit
If interference is detected by the receiver it will signal the transmitter to change frequencies
was E8C11
What spread- spectrum communications technique uses a high speed binary bit stream to shift the phase of an RF carrier?
Frequency hopping
Direct sequence
Binary phase-shift keying
Phase compandored spread- spectrum
was E2C09
How does the spread- spectrum technique of frequency hopping work?
If interference is detected by the receiver it will signal the transmitter to change frequencies
If interference is detected by the receiver it will signal the transmitter to wait until the frequency is clear
A pseudo-random binary bit stream is used to shift the phase of an RF carrier very rapidly in a particular sequence
The frequency of the transmitted signal is changed very rapidly according to a particular sequence also used by the receiving station
- NEW -
What is the primary effect of extremely short rise or fall time on a CW signal?
More difficult to copy
The generation of RF harmonics
The generation of key clicks
Limits data speed
- NEW -
What is the most common method of reducing key clicks?
Increase keying waveform rise and fall times
Low-pass filters at the transmitter output
Reduce keying waveform rise and fall times
High-pass filters at the transmitter output
- NEW -
Which of the following indicates likely overmodulation of an AFSK signal such as PSK or MFSK?
High reflected power
Strong ALC action
Harmonics on higher bands
Rapid signal fading
- NEW -
What is a common cause of overmodulation of AFSK signals?
Excessive numbers of retries
Ground loops
Bit errors in the modem
Excessive transmit audio levels
- NEW -
What parameter might indicate that excessively high input levels are causing distortion in an AFSK signal?
Signal to noise ratio
Baud rate
Repeat Request Rate (RRR)
Intermodulation Distortion (IMD)
- NEW -
What is considered a good minimum IMD level for an idling PSK signal?
+10 dB
+15 dB
-20 dB
-30 dB
was E8C02
What are some of the differences between the Baudot digital code and ASCII?
Baudot uses four4 data bits per character, ASCII uses seven or eight7 or 8; Baudot uses one1 character as a letters/figures shift code, ASCII has no shiftletters/figures code
Baudot uses five5 data bits per character, ASCII uses seven or eight7 or 8; Baudot uses two2 characters as letters/figures shift codes, ASCII has no letters/figures shift code
Baudot uses six6 data bits per character, ASCII uses seven or eight7 or 8; Baudot has no letters/figures shift code, ASCII uses two characters as 2 letters/figures shift codes
Baudot uses seven7 data bits per character, ASCII uses eight8; Baudot has no letters/figures shift code, ASCII uses two characters as 2 letters/figures shift codes
was E8C03
What is one advantage of using the ASCII code for data communications?
It includes built- in error- correction features
It contains fewer information bits per character than any other code
It is possible to transmit both upper and lower case text
It uses one character as a shift code to send numeric and special characters
was E8C12
What is the advantage of including a parity bit with an ASCII character stream?
Faster transmission rate
The signal can overpower interfering signals
Foreign language characters can be sent
Some types of errors can be detected
Subelement E9
ANTENNAS AND TRANSMISSION LINES
Removed questions: 7
New questions: 8
Updated questions: 4
Total questions: 112
Section E9A
Isotropic and gain antennas: definitions; uses; radiation patterns; Basic antennaAntenna parameters: radiation resistance and reactance, gain, gain, beamwidth, efficiency, beamwidth; effective radiated power, polarization, efficiency
Removed questions: 1
New questions: 0
Updated questions: 3
Total questions: 18
REMOVED
How much gain does a 1/2-wavelength dipole in free space have compared to an isotropic antenna?
1.55 dB
2.15 dB
3.05 dB
4.30 dB
Which of the following What describes an isotropic antenna?
A grounded antenna used to measure earth conductivity
A horizontally polarized antenna used to compare Yagi antennas
A theoretical antenna used as a reference for antenna gain
A spacecraft antenna used to direct signals toward the earth
was E9A03
Which of the following antennas What antenna has no gain in any direction?
Quarter-wave vertical
Yagi
Half-wave dipole
Isotropic antenna
was E9A04
Why would one need to know the feed point impedance of an antenna?
To match impedances in order to minimize standing wave ratio on the transmission line
To measure the near-field radiation density from a transmitting antenna
To calculate the front-to-side ratio of the antenna
To calculate the front-to-back ratio of the antenna
was E9A05
Which of the following factors may affect the feed point impedance of an antenna?
Transmission-line length
Antenna height, conductor length/diameter ratio and location of nearby conductive objects
The settings of an antenna tuner at the transmitterConstant feed point impedance
Sunspot activity and time of day
was E9A06
What is included in the total resistance of an antenna system?
Radiation resistance plus space impedance
Radiation resistance plus transmission resistance
Transmission-line resistance plus radiation resistance
Radiation resistance plus ohmic resistance
was E9D03
How does the beamwidth of an antenna vary as the gain is increased?
It increases geometrically
It increases arithmetically
It is essentially unaffected
It decreases
was E9A08
What is meant by antenna gain?
The ratio relatingof the radiated signal strength of an antenna in the direction of maximum radiation to that of a reference antenna
The ratio of the signal in the forward direction to that in the opposite direction
The ratio of the amount of power radiated by an antenna compared to the transmitter output power
The final amplifier gain minus the transmission- line losses, including any phasing lines present
was E9A09
What is meant by antenna bandwidth?
Antenna length divided by the number of elements
The frequency range over which an antenna satisfies a performance requirement
The angle between the half-power radiation points
The angle formed between two imaginary lines drawn through the element ends
was E9A10
How is antenna efficiency calculated?
(radiation resistance / transmission resistance) x 100 percent%
(radiation resistance / total resistance) x 100 percent%
(total resistance / radiation resistance) x 100 percent%
(effective radiated power / transmitter output) x 100 percent%
was E9A11
Which of the following choices is a way to improve the efficiency of a ground-mounted quarter-wave vertical antenna?
Install a good radial system
Isolate the coax shield from ground
Shorten the radiating element
Reduce the diameter of the radiating element
was E9A12
Which of the following factors determines ground losses for a ground-mounted vertical antenna operating in the 3- MHz to 30 MHz range?
The standing- wave ratio
Distance from the transmitter
Soil conductivity
Take-off angle
was E9A13
How much gain does an antenna have compared to a 1/2-wavelength dipole when it has 6 dB gain over an isotropic antenna?
3.85 dB
6.0 dB
8.15 dB
2.79 dB
was E9A14
How much gain does an antenna have compared to a 1/2-wavelength dipole when it has 12 dB gain over an isotropic antenna?
6.17 dB
9.85 dB
12.5 dB
14.15 dB
was E9A15
What is meant by the radiation resistance of an antenna?
The combined losses of the antenna elements and feed line
The specific impedance of the antenna
The value of a resistance that would dissipate the same amount of power as that radiated from an antenna
The resistance in the atmosphere that an antenna must overcome to be able to radiate a signal
was E9H01
What is the effective radiated power relative to a dipole of a repeater station with 150 watts transmitter power output, 2- dB feed line loss, 2.2- dB duplexer loss, and 7- dBd antenna gain?
1977 watts
78.7 watts
420 watts
286 watts
was E9H02
What is the effective radiated power relative to a dipole of a repeater station with 200 watts transmitter power output, 4- dB feed line loss, 3.2- dB duplexer loss, 0.8- dB circulator loss, and 10- dBd antenna gain?
317 watts
2000 watts
126 watts
300 watts
was E9H03
What is the effective isotropic radiated power of a repeater station with 200 watts transmitter power output, 2- dB feed line loss, 2.8- dB duplexer loss, 1.2- dB circulator loss, and 7- dBi antenna gain?
159 watts
252 watts
632 watts
63.2 watts
was E9H04
What term describes station output, including the transmitter, antenna and everything in between, when considering transmitter power and system taking into account all gains and losses?
Power factor
Half-power bandwidth
Effective radiated power
Apparent power
Section E9B
Antenna patterns: E and H plane patterns; gain as a function of pattern; antenna design (computer modeling of antennas); Yagi antennas
Removed questions: 1
New questions: 0
Updated questions: 0
Total questions: 16
REMOVED
If the boom of a Yagi antenna is lengthened and the elements are properly retuned, what usually occurs?
The gain increases
The SWR decreases
The front-to-back ratio increases
The gain bandwidth decreases rapidly
In the antenna radiation pattern shown in Figure E9-1, what is the 3 dB beam-width?-dB beamwidth?
75 degrees
50 degrees
25 degrees
30 degrees
In the antenna radiation pattern shown in Figure E9-1, what is the front-to-back ratio?
36 dB
18 dB
24 dB
14 dB
In the antenna radiation pattern shown in Figure E9-1, what is the front-to-side ratio?
12 dB
14 dB
18 dB
24 dB
What may occur when a directional antenna is operated at different frequencies within the band for which it was designed?
Feed point impedance may become negative
The E-field and H-field patterns may reverse
Element spacing limits could be exceeded
The gain may change depending on frequency
was E9C07
What type of antenna pattern over real ground is shown in Figure E9-2?
Elevation
Azimuth
Radiation resistance
Polarization
was E9C08
What is the elevation angle of peak response in the antenna radiation pattern shown in Figure E9-2?
45 degrees
75 degrees
7.5 degrees
25 degrees
How does the total amount of radiation emitted by a directional gain antenna compare with the total amount of radiation emitted from an isotropic antenna, assuming each is driven by the same amount of power?
The total amount of radiation from the directional antenna is increased by the gain of the antenna
The total amount of radiation from the directional antenna is stronger by its front to -to-back ratio
They are the same
The radiation from the isotropic antenna is 2.15 dB stronger than that from the directional antenna
How can the approximate beamwidthbeam-width in a given plane of a directional antenna be determined?
Note the two points where the signal strength of the antenna is 3 dB less than maximum and compute the angular difference
Measure the ratio of the signal strengths of the radiated power lobes from the front and rear of the antenna
Draw two imaginary lines through the ends of the elements and measure the angle between the lines
Measure the ratio of the signal strengths of the radiated power lobes from the front and side of the antenna
What type of computer program technique is commonly used for modeling antennas?
Graphical analysis
Method of Moments
Mutual impedance analysis
Calculus differentiation with respect to physical properties
What is the principle of a Method of Moments analysis?
A wire is modeled as a series of segments, each having a uniform value of current
A wire is modeled as a single sine-wave current generator
A wire is modeled as a series of points, each having a distinct location in space
A wire is modeled as a series of segments, each having a distinct value of voltage across it
What is a disadvantage of decreasing the number of wire segments in an antenna model below the guideline of 10 segments per half-wavelength?
Ground conductivity will not be accurately modeled
The resulting design will favor radiation of harmonic energy
The computed feed point impedance may be incorrect
The antenna will become mechanically unstable
What is the far- field of an antenna?
The region of the ionosphere where radiated power is not refracted
The region where radiated power dissipates over a specified time period
The region where radiated field strengths are obstructed by objects of reflection
The region where the shape of the antenna pattern is independent of distance
What does the abbreviation NEC stand for when applied to antenna modeling programs?
Next Element Comparison
Numerical ElectromagneticsElectromagnetic Code
National Electrical Code
Numeric Electrical Computation
What type of information can be obtained by submitting the details of a proposed new antenna to a modeling program?
SWR vs. frequency charts
Polar plots of the far- field elevation and azimuth patterns
Antenna gain
All of these choices are correct
was E9C09
What is the front-to-back ratio of the radiation pattern shown in Figure E9-2?
15 dB
28 dB
3 dB
24 dB
was E9C10
How many elevation lobes appear in the forward direction of the antenna radiation pattern shown in Figure E9-2?
4
3
1
7
Section E9C
Wire and phased verticalarray antennas: beverage antennas; rhombic antennas; effects of ground reflections; e-off angles; Practical wire antennas: Zepps, OCFD, loopselevation above real ground; ground effects as related to polarization; take-off angles
Removed questions: 2
New questions: 5
Updated questions: 0
Total questions: 15
REMOVED
Which of the following describes a basic unterminated rhombic antenna?
Unidirectional; four-sides, each side one quarter-wavelength long; terminated in a resistance equal to its characteristic impedance
Bidirectional; four-sides, each side one or more wavelengths long; open at the end opposite the transmission line connection
Four-sides; an LC network at each corner except for the transmission connection;
Four-sides, each of a different physical length
REMOVED
What are the disadvantages of a terminated rhombic antenna for the HF bands?
The antenna has a very narrow operating bandwidth
The antenna produces a circularly polarized signal
The antenna requires a large physical area and 4 separate supports
The antenna is more sensitive to man-made static than any other type
What is the radiation pattern of two 1/4-wavelength vertical antennas spaced 1/2-wavelength apart and fed 180 degrees out of phase?
A cardioidCardioid
Omni-directionalOmnidirectional
A figure-8 broadside to the axis of the array
A figure-8 oriented along the axis of the array
What is the radiation pattern of two 1/4- wavelength vertical antennas spaced 1/4- wavelength apart and fed 90 degrees out of phase?
A cardioidCardioid
A figure-8 end-fire along the axis of the array
A figure-8 broadside to the axis of the array
Omni-directionalOmnidirectional
What is the radiation pattern of two 1/4- wavelength vertical antennas spaced 1/2-a 1/2 wavelength apart and fed in phase?
Omni-directionalOmnidirectional
A cardioidCardioid
A Figure-8 broadside to the axis of the array
A Figure-8 end-fire along the axis of the array
- NEW -
What happens to the radiation pattern of an unterminated long wire antenna as the wire length is increased?
The lobes become more perpendicular to the wire
The lobes align more in the direction of the wire
The vertical angle increases
The front-to-back ratio decreases
- NEW -
What is an OCFD antenna?
A dipole feed approximately 1/3 the way from one end with a 4:1 balun to provide multiband operation
A remotely tunable dipole antenna using orthogonally controlled frequency diversity
An eight band dipole antenna using octophase filters
A multiband dipole antenna using one-way circular polarization for frequency diversity
What is the effect of a terminating resistor on a rhombic antenna?
It reflects the standing waves on the antenna elements back to the transmitter
It changes the radiation pattern from bidirectional to unidirectional
It changes the radiation pattern from horizontal to vertical polarization
It decreases the ground loss
was E9D10
What is the approximate feed point impedance at the center of a two-wire folded dipole antenna?
300 ohms
72 ohms
50 ohms
450 ohms
was E9A07
What is a folded dipole antenna?
A dipole one-quarter wavelength long
A type of ground-plane antenna
A dipole constructed fromconsisting of one wavelength of wire forming a very thin loop
A dipole configured to provide forward gain
- NEW -
What is a G5RV antenna?
A multi-band dipole antenna fed with coax and a balun through a selected length of open wire transmission line
A multi-band trap antenna
A phased array antenna consisting of multiple loops
A wide band dipole using shorted coaxial cable for the radiating elements and fed with a 4:1 balun
- NEW -
Which of the following describes a Zepp antenna?
A dipole constructed from zip cord
An end fed dipole antenna
An omni-directional antenna commonly used for satellite communications
A vertical array capable of quickly changing the direction of maximum radiation by changing phasing lines
How is the far-field elevation pattern of a vertically polarized antenna affected by being mounted over seawater versus rocky ground?
The low-angle radiation decreases
The high-angle radiation increases
Both the high-angle and low-angle radiation decrease
The low-angle radiation increases
- NEW -
Which of the following describes an extended double Zepp antenna?
A wideband vertical antenna constructed from precisely tapered aluminum tubing
A portable antenna erected using two push support poles
A center fed 1.25 wavelength antenna (two 5/8 wave elements in phase)
An end fed folded dipole antenna
What is the main effect of placing a vertical antenna over an imperfect ground?
It causes increased SWR
It changes the impedance angle of the matching network
It reduces low-angle radiation
It reduces losses in the radiating portion of the antenna
was E3C10
How does the performance of a horizontally polarized antenna mounted on the side of a hill compare with the same antenna mounted on flat ground?
The main lobe takeoff angle increases in the downhill direction
The main lobe takeoff angle decreases in the downhill direction
The horizontal beam width decreases in the downhill direction
The horizontal beam width increases in the uphill direction
was E3C07
How does the radiation pattern of a horizontally polarized 3-element beam antenna vary with its height above ground?
The main lobe takeoff angle increases with increasing height
The main lobe takeoff angle decreases with increasing height
Why is it desirable for a ground-mounted satellite communications antenna system to be able to move in both azimuth and elevation?
In order to track the satellite as it orbits the Earth
So the antenna can be pointed away from interfering signals
So the antenna can be positioned to cancel the effects of Faraday rotation
To rotate antenna polarization to match that of the satellite
REMOVED
What is one advantage of using a trapped antenna?
It has high directivity in the higher-frequency bands
It has high gain
It minimizes harmonic radiation
It may be used for multiband operation
How does the gain of an ideal parabolic dish antenna change when the operating frequency is doubled?
Gain does not change
Gain is multiplied by 0.707
Gain increases by 6 dB
Gain increases by 3 dB
How can linearly polarized Yagi antennas be used to produce circular polarization?
Stack two Yagis, fed 90 degrees out of phase, to form an array with the respective elements in parallel planes
Stack two Yagis, fed in phase, to form an array with the respective elements in parallel planes
Arrange two Yagis perpendicular to each other with the driven elements at the same point on the boom and fed 90 degrees out of phase
Arrange two Yagis collinear to each other, with the driven elements fed 180 degrees out of phase
was E9D05
Where should a high- Q loading coil be placed to minimize losses in a shortened vertical antenna?
Near the center of the vertical radiator
As low as possible on the vertical radiator
As close to the transmitter as possible
At a voltage node
was E9D06
Why should an HF mobile antenna loading coil have a high ratio of reactance to resistance?
To swamp out harmonics
To maximize losses
To minimize losses
To minimize the Q
was E9D07
What is a disadvantage of using a multiband trapped antenna?
It might radiate harmonics
It radiates the harmonics and fundamental equally well
It is too sharply directional at lower frequencies
It must be neutralized
was E9D08
What happens to the bandwidth of an antenna as it is shortened through the use of loading coils?
It is increased
It is decreased
No change occurs
It becomes flat
was E9D09
What is an advantage of using top loading in a shortened HF vertical antenna?
Lower Q
Greater structural strength
Higher losses
Improved radiation efficiency
- NEW -
What happens as the Q of an antenna increases?
SWR bandwidth increases
SWR bandwidth decreases
Gain is reduced
More common-mode current is present on the feed line
was E9D11
What is the function of a loading coil as used withused as part of an HF mobile antenna?
To increase the SWR bandwidth
To lower the losses
To lower the Q
To cancel capacitive reactance
was E9D13
What happens to feed point impedance at the base of a fixed- length HF mobile antenna as the frequency of operation is lowered?
The radiation resistance decreases and the capacitive reactance decreases
The radiation resistance decreases and the capacitive reactance increases
The radiation resistance increases and the capacitive reactance decreases
The radiation resistance increases and the capacitive reactance increases
was E9D14
Which of the following types of conductorconductors would be best for minimizing losses in a station's RF ground system?
A resistive wire, such as a spark plug wire
A wide flat copper strap
A cable with 6 or 7 18-six or seven 18 gauge conductors in parallel
A single 12 gauge or 10- gauge stainless steel wire
was E9D15
Which of the following would provide the best RF ground for your station?
A 50-A 50 ohm resistor connected to ground
An electrically- short connection to a metal water pipe
An electrically- short connection to 3 or 4 interconnected ground rods driven into the Earth
An electrically- short connection to 3 or 4 interconnected ground rods via a series RF choke
was E9B05
What usually occurs if a Yagi antenna is designed solely for maximum forward gain?
The front-to-back ratio increases
The front-to-back ratio decreases
The frequency response is widened over the whole frequency band
The SWR is reduced
Section E9E
Matching: matching antennas to feed lines; phasing lines; power dividers
Removed questions: 1
New questions: 1
Updated questions: 1
Total questions: 13
REMOVED
What is the equivalent lumped-constant network for a hairpin matching system on a 3-element Yagi?
Pi network
Pi-L network
L network
Parallel-resonant tank
What system matches a high-higher impedance transmission line to a lower impedance antenna by connecting the line to the driven element in two places spaced a fraction of a wavelength each side of element center?
The gamma matching system
The delta matching system
The omega matching system
The stub matching system
What is the name of an antenna matching system that matches an unbalanced feed line to an antenna by feeding the driven element both at the center of the element and at a fraction of a wavelength to one side of center?
The gamma match
The delta match
The epsilon match
The stub match
What is the name of the matching system that uses a section of transmission line connected in parallel with the feed line at or near the feed point?
The gamma match
The delta match
The omega match
The stub match
What is the purpose of the series capacitor in a gamma-type antenna matching network?
To provide DC isolation between the feed line and the antenna
To cancel the inductive reactance of the matching network
To provide a rejection notch to preventthat prevents the radiation of harmonics
To transform the antenna impedance to a higher value
How must the driven element in a 3-element Yagi be tuned to use a hairpin matching system?
The driven element reactance must be capacitive
The driven element reactance must be inductive
The driven element resonance must be lower than the operating frequency
The driven element radiation resistance must be higher than the characteristic impedance of the transmission line
- NEW -
What is the equivalent lumped-constant network for a hairpin matching system of a 3-element Yagi?
Pi-network
Pi-L-network
A shunt inductor
A series capacitor
What term best describes the interactions at the load end of a mismatched transmission line?
Characteristic impedance
Reflection coefficient
Velocity factor
Dielectric constant
Which of the following measurements is characteristic of a mismatched transmission line?
An SWR less than 1:1
A reflection coefficient greater than 1
A dielectric constant greater than 1
An SWR greater than 1:1
Which of these matching systems is an effective method of connecting a 50- ohm coaxial cable feed line to a grounded tower so it can be used as a vertical antenna?
Double-bazooka match
Hairpin match
Gamma match
All of these choices are correct
Which of these choices is an effective way to match an antenna with a 100- ohm feed point impedance to a 50- ohm coaxial cable feed line?
Connect a 1/4-wavelength open stub of 300- ohm twin-lead in parallel with the coaxial feed line where it connects to the antenna
Insert a 1/2 wavelength piece of 300- ohm twin-lead in series between the antenna terminals and the 50- ohm feed cable
Insert a 1/4-wavelength piece of 75- ohm coaxial cable transmission line in series between the antenna terminals and the 50- ohm feed cable
Connect 1/2 wavelength shorted stub of 75- ohm cable in parallel with the 50- ohm cable where it attaches to the antenna
What is an effective way of matching a feed line to a VHF or UHF antenna when the impedances of both the antenna and feed line are unknown?
Use a 50- ohm 1:1 balun between the antenna and feed line
Use the "universal stub" matching technique
Connect a series-resonant LC network across the antenna feed terminals
Connect a parallel-resonant LC network across the antenna feed terminals
What is the primary purpose of a phasing line when used with an antenna having multiple driven elements?
It ensures that each driven element operates in concert with the others to create the desired antenna pattern
It prevents reflected power from traveling back down the feed line and causing harmonic radiation from the transmitter
It allows single-band antennas to operate on other bands
It makes sure the antenna has a low-angle radiation pattern
What is the purpose ofa use for a Wilkinson divider?
It divides the operating frequency of a transmitter signal so it can be used on a lower frequency band
It is used to feed high-impedance antennas from a low-impedance source
It is used to divide power equally between two 50 ohm loads while maintaining 50 ohm input impedanceIt divides power equally among multiple loads while preventing changes in one load from disturbing power flow to the others
It is used to feed low-impedance loads from a high-impedance source
Section E9F
Transmission lines: characteristics of open and shorted feed lines; 1/8 wavelength; 1/4 wavelength; 1/2 wavelength; feed lines: coax versus open-wire; velocity factor; electrical length; coaxial cable dielectrics; velocity factor
Removed questions: 0
New questions: 0
Updated questions: 0
Total questions: 16
What is the velocity factor of a transmission line?
The ratio of the characteristic impedance of the line to the terminating impedance
The index of shielding for coaxial cable
The velocity of the wave in the transmission line multiplied by the velocity of light in a vacuum
The velocity of the wave in the transmission line divided by the velocity of light in a vacuum
Which of the following determines the velocity factor of a transmission line?
The termination impedance
The line length
Dielectric materials used in the line
The center conductor resistivity
Why is the physical length of a coaxial cable transmission line shorter than its electrical length?
Skin effect is less pronounced in the coaxial cable
The characteristic impedance is higher in a parallel feed line
The surge impedance is higher in a parallel feed line
Electrical signals move more slowly in a coaxial cable than in air
What is the typical velocity factor for a coaxial cable with solid polyethylene dielectric?
2.70
0.66
0.30
0.10
What is the approximate physical length of a solid polyethylene dielectric coaxial transmission line that is electrically one-quarter wavelength long at 14.1 MHz?
20 meters
2.3 meters
3.5 meters
0.2 meters
What is the approximate physical length of an air-insulated, parallel conductor transmission line that is electrically one-half wavelength long at 14.10 MHz?
15 meters
20 meters
10 meters
71 meters
How does ladder line compare to small-diameter coaxial cable such as RG-58 at 50 MHz?
Lower loss
Higher SWR
Smaller reflection coefficient
Lower velocity factor
What is the term for the ratio of the actual speed at which a signal travels through a transmission line to the speed of light in a vacuum?
Velocity factor
Characteristic impedance
Surge impedance
Standing wave ratio
What is the approximate physical length of a solid polyethylene dielectric coaxial transmission line that is electrically one-quarter wavelength long at 7.2 MHz?
10 meters
6.9 meters
24 meters
50 meters
What impedance does a 1/8- wavelength transmission line present to a generator when the line is shorted at the far end?
A capacitive reactance
The same as the characteristic impedance of the line
An inductive reactance
The same as the input impedance to the final generator stage
What impedance does a 1/8- wavelength transmission line present to a generator when the line is open at the far end?
The same as the characteristic impedance of the line
An inductive reactance
A capacitive reactance
The same as the input impedance of the final generator stage
What impedance does a 1/4- wavelength transmission line present to a generator when the line is open at the far end?
The same as the characteristic impedance of the line
The same as the input impedance to the generator
Very high impedance
Very low impedance
What impedance does a 1/4- wavelength transmission line present to a generator when the line is shorted at the far end?
Very high impedance
Very low impedance
The same as the characteristic impedance of the transmission line
The same as the generator output impedance
What impedance does a 1/2- wavelength transmission line present to a generator when the line is shorted at the far end?
Very high impedance
Very low impedance
The same as the characteristic impedance of the line
The same as the output impedance of the generator
What impedance does a 1/2- wavelength transmission line present to a generator when the line is open at the far end?
Very high impedance
Very low impedance
The same as the characteristic impedance of the line
The same as the output impedance of the generator
Which of the following is a significant difference between foam- dielectric coaxial cable and solid- dielectric cable, assuming all other parameters are the same?
Reduced Foam dielectric has lower safe operating voltage limits
Reduced losses Foam dielectric has lower loss per unit of length
Higher Foam dielectric has higher velocity factor
All of these choices are correct
Section E9G
The Smith chart
Removed questions: 0
New questions: 0
Updated questions: 0
Total questions: 11
Which of the following can be calculated using a Smith chart?
Impedance along transmission lines
Radiation resistance
Antenna radiation pattern
Radio propagation
What type of coordinate system is used in a Smith chart?
Voltage circles and current arcs
Resistance circles and reactance arcs
Voltage lines and current chords
Resistance lines and reactance chords
Which of the following is often determined using a Smith chart?
Beam headings and radiation patterns
Satellite azimuth and elevation bearings
Impedance and SWR values in transmission lines
Trigonometric functions
What are the two families of circles and arcs that make up a Smith chart?
Resistance and voltage
Reactance and voltage
Resistance and reactance
Voltage and impedance
What type of chart is shown in Figure E9-3?
Smith chart
Free-Free space radiation directivity chart
Elevation angle radiation pattern chart
Azimuth angle radiation pattern chart
On the Smith chart shown in Figure E9-3, what is the name for the large outer circle on which the reactance arcs terminate?
Prime axis
Reactance axis
Impedance axis
Polar axis
On the Smith chart shown in Figure E9-3, what is the only straight line shown?
The reactance axis
The current axis
The voltage axis
The resistance axis
What is the process of normalization with regard to a Smith chart?
Reassigning resistance values with regard to the reactance axis
Reassigning reactance values with regard to the resistance axis
Reassigning impedance values with regard to the prime center
Reassigning prime center with regard to the reactance axis
What third family of circles is often added to a Smith chart during the process of solving problems?
Standing- wave ratio circles
Antenna-length circles
Coaxial-length circles
Radiation-pattern circles
What do the arcs on a Smith chart represent?
Frequency
SWR
Points with constant resistance
Points with constant reactance
How are the wavelength scales on a Smith chart calibrated?
In fractions of transmission line electrical frequency
In fractions of transmission line electrical wavelength
In fractions of antenna electrical wavelength
In fractions of antenna electrical frequency
Section E9H
Effective radiated power; system gains and losses; radio direction finding Receiving Antennas: radio direction finding antennas; Beverage Antennas; specialized receiving antennas; longwire receiving antennas
Removed questions: 0
New questions: 1
Updated questions: 0
Total questions: 10
was E9C12
When constructing a Beverage antenna, which of the following factors should be included in the design to achieve good performance at the desired frequency?
Its overall length must not exceed 1/4 wavelength
It must be mounted more than 1 wavelength above ground
It should be configured as a four-sided loop
It should be one or more wavelengths long
- NEW -
Which is generally true for low band (160 meter and 80 meter) receiving antennas?
Atmospheric noise is so high that gain over a dipole is not important
They must be erected at least 1/2 wavelength above the ground to attain good directivity
Low loss coax transmission line is essential for good performance
All of these choices are correct
was E9H12
What is an advantage of using a shielded loop antenna for direction finding?
It automatically cancels ignition noise pickup in mobile installations
It is electro- statically balanced against ground, giving better nulls
It eliminates tracking errors caused by strong out-of-band signals
It allows stations to communicate without giving away their position
What is the main drawback of a wire-loop antenna for direction finding?
It has a bidirectional pattern
It is non-rotatable
It receives equally well in all directions
It is practical for use only on VHF bands
What is the triangulation method of direction finding?
The geometric angleangles of sky waves from the source are used to determine its position
A fixed receiving station plots three headings fromto the signal source on a map
Antenna headings from several different receiving locations are used to locate the signal source
A fixed receiving station uses three different antennas to plot the location of the signal source
Why is it advisable to use an RF attenuator on a receiver being used for direction finding?
It narrows the bandwidth of the received signal to improve signal to noise ratio
It compensates for the effects of an isotropic antenna, thereby improving directivity
It reduces loss of received signals caused by antenna pattern nulls, thereby increasing sensitivity
It prevents receiver overload which could make it difficult to determine peaks or nulls
What is the function of a sense antenna?
It modifies the pattern of a DF antenna array to provide a null in one direction
It increases the sensitivity of a DF antenna array
It allows DF antennas to receive signals at different vertical angles
It provides diversity reception that cancels multipath signals
Which of the following describes the construction of a receiving loop antenna?
A large circularly- polarized antenna
A small coil of wire tightly wound around a toroidal ferrite core
One or more turns of wire wound in the shape of a large open coil
A vertical antenna coupled to a feed line through an inductive loop of wire
How can the output voltage of a multi-multiple turn receiving loop antenna be increased?
By reducing the permeability of the loop shield
By increasing the number of wire turns in the loop and reducing the area of the loop structure
By winding adjacent turns in opposing directions
By increasing either the number of wire turns in the loop or the area of the loop structure or both
What characteristic of a cardioid- pattern antenna is useful for direction finding?
What, if any, are the differences between the radiation produced by radioactive materials and the electromagnetic energy radiated by an antenna?
There is no significant difference between the two types of radiation
Only radiation produced by radioactivity can injure human beings
Radioactive materials emit ionizing radiation, while RF signals have less energy and can only cause heating
Radiation from an antenna will damage unexposed photographic film but ordinary radioactive materials do not cause this problem
- NEW -
What is the primary function of an external earth connection or ground rod?
Reduce received noise
Lightning protection
Reduce RF current flow between pieces of equipment
Reduce RFI to telephones and home entertainment systems
When evaluating RF exposure levels from your station at a neighbor's home, what must you do?
Make sure signals from your station are less than the controlled MPE limits
Make sure signals from your station are less than the uncontrolled MPE limits
You need only evaluate exposure levels on your own property
Advise your neighbors of the results of your tests
Which of the following would be a practical way to estimate whether the RF fields produced by an amateur radio station are within permissible MPE limits?
Use a calibrated antenna analyzer
Use a hand calculator plus Smith-chart equations to calculate the fields
Use an antenna modeling program to calculate field strength at accessible locations
All of the choices are correct
When evaluating a site with multiple transmitters operating at the same time, the operators and licensees of which transmitters are responsible for mitigating over-exposure situations?
Only the most powerful transmitter
Only commercial transmitters
Each transmitter that produces 5% percent or more of its MPE exposure limit at accessible locations
Each transmitter operating with a duty-cycle greater than 50 percent%
What is one of the potential hazards of using microwaves in the amateur radio bands?
Microwaves are ionizing radiation
The high gain antennas commonly used can result in high exposure levels
Microwaves often travel long distances by ionospheric reflection
The extremely high frequency energy can damage the joints of antenna structures
Why are there separate electric (E) and magnetic (H) field MPE limits?
The body reacts to electromagnetic radiation from both the E and H fields
Ground reflections and scattering make the field impedance vary with location
E field and H field radiation intensity peaks can occur at different locations
All of these choices are correct
How may dangerous levels of carbon monoxide from an emergency generator be detected?
By the odor
Only with a carbon monoxide detector
Any ordinary smoke detector can be used
By the yellowish appearance of the gas
What does SAR measure?
Synthetic Aperture Ratio of the human body
Signal Amplification Rating
The rate at which RF energy is absorbed by the body
The rate of RF energy reflected from stationary terrain
Which insulating material commonly used as a thermal conductor for some types of electronic devices is extremely toxic if broken or crushed and the particles are accidentally inhaled?
Mica
Zinc oxide
Beryllium Oxide
Uranium HexafluorideHexaflouride
What toxic material found may be present in some electronic components such as high- voltage capacitors and transformers? is considered toxic?
Polychlorinated Biphenylsbiphenyls
Polyethylene
Polytetrafluroethylene
Polymorphic silicon
Which of the following injuries can result from using high-power UHF or microwave transmitters?
Hearing loss caused by high voltage corona discharge
Blood clotting from the intense magnetic field
Localized heating of the body from RF exposure in excess of the MPE limits