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Subelement T8
Modulation modes: amateur satellite operation; operating activities; non-voice communications
Section T8C
Operating activities: radio direction finding; radio control; contests; linking over the Internet; grid locators
Which of the following methods is used to locate sources of noise interference or jamming?
  • Echolocation
  • Doppler radar
  • Correct Answer
    Radio direction finding
  • Phase locking

When there is radio interference, whether intentional or unintentional, you can use radio direction finding to track down the interfering noise source. This can be a directional antenna or some other means of determining where the offender is located. After you have a direction from two locations you can pinpoint where to go to find your culprit.

Last edited by aj9r. Register to edit

Tags: troubleshooting noise and interference definitions activities arrl chapter 6 arrl module 14

Which of these items would be useful for a hidden transmitter hunt?
  • Calibrated SWR meter
  • Correct Answer
    A directional antenna
  • A calibrated noise bridge
  • All of these choices are correct

A hidden transmitter hunt, also known as a "Fox Hunt", involves having a hidden transmitter (the "fox") that transmits periodically while other operators attempt to find it. The simplest way to do this is to watch the signal strength meter on your radio while rotating a directional antenna to find out from which direction the signal is strongest.

A calibrated SWR meter might be helpful for tuning your antenna, but for a fox hunt you may actually want an out of tune antenna -- since it wouldn't receive as well, it would be easier to see where the signal is coming from =]

Last edited by kd7bbc. Register to edit

Tags: directional antenna activities arrl chapter 6 arrl module 14

What popular operating activity involves contacting as many stations as possible during a specified period of time?
  • Correct Answer
  • Net operations
  • Public service events
  • Simulated emergency exercises

Contests are a very popular and fun use of HF. During a contest, all operators participating keep a log of what stations they have contacted and rather than having a conversation with them will exchange the minimum information required to confirm the contact and for the contest rules with as many stations as possible for the duration of the contest.

Last edited by loubarchey. Register to edit

Tags: activities arrl chapter 6 arrl module 14

Which of the following is good procedure when contacting another station in a radio contest?
  • Be sure to sign only the last two letters of your call if there is a pileup calling the station
  • Work the station twice to be sure that you are in his log
  • Correct Answer
    Send only the minimum information needed for proper identification and the contest exchange
  • All of these choices are correct

Since the purpose of a radio contest is to see how many stations you can contact during the duration of a contest, the most important things are to make sure that both stations have accurately recorded the identification of the stations (so you should certainly not use only two letters of your call) and that you don't take more of their time than necessary, thus slowing them down (and so you shouldn't work the station more than once).

Always be brief, but also be concise and complete.

Last edited by seriousworm. Register to edit

Tags: activities best practices arrl chapter 6 arrl module 14

What is a grid locator?
  • Correct Answer
    A letter-number designator assigned to a geographic location
  • A letter-number designator assigned to an azimuth and elevation
  • An instrument for neutralizing a final amplifier
  • An instrument for radio direction finding

A Grid Locator, also known as a Grid Square, is basically a shorthand for location based on latitude and longitude. For more information visit http://www.arrl.org/grid- squares

Last edited by rccapps. Register to edit

Tags: definitions arrl chapter 6 arrl module 13

How is access to an IRLP node accomplished?
  • By obtaining a password which is sent via voice to the node
  • Correct Answer
    By using DTMF signals
  • By entering the proper Internet password
  • By using CTCSS tone codes

IRLP: Internet Radio Linking Project DTMF: Dual Tone - Multi Frequency

DTMF is the generic term for Touch-Tone, which is a registered trademark of ATT. Your touch-toneĀ® phone is technically a DTMF generator that produces DTMF tones as you press the buttons.

Communicating with an IRLP node requires the keying of DTMF signals, sent manually by key pad or automatically.

A repeater could require CTCSS (Continuous Tone-Coded Squelch System) or DCS (Digital Code Squelch) to communicate with it, regardless of IRLP, but IRLP itself does not depend on CTCSS or DCS tones.

Also, some repeaters require a special password that you send along with the DTMF signals, but the IRLP access is still accomplished by using DTMF signals.

Last edited by shivanshyshukla. Register to edit

Tags: arrl chapter 6 arrl module 13

What is the maximum power allowed when transmitting telecommand signals to radio controlled models?
  • 500 milliwatts
  • Correct Answer
    1 watt
  • 25 watts
  • 1500 watts

Telecommands are limited to a maximum power as the transmitted signals do not have, or require, any form of regular station identification. A low power value, such as 1 watt, is specified in order to limit the distance which the signal will propagate. All other forms of communication in the amateur authorized bands require regular intervals of station identification.

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Tags: transmit power radio operation arrl chapter 6 arrl module 14

What is required in place of on-air station identification when sending signals to a radio control model using amateur frequencies?
  • Voice identification must be transmitted every 10 minutes
  • Morse code ID must be sent once per hour
  • Correct Answer
    A label indicating the licensee's name, call sign and address must be affixed to the transmitter
  • A flag must be affixed to the transmitter antenna with the station call sign in 1 inch high letters or larger

When using a radio control model, you can't exactly transmit your callsign every 10 minutes. First, really read the question (emphasis added) -- "What is required in place of on-air station identification." Since we are looking for something in place of on-air identification, you know that it can't be some form of on-air identification, which eliminates two of the answers. From a more practical perspective, just imagine what would happen to your model aircraft if every ten minutes there was a 20 second period in which you couldn't control it because you were identifying! What if that occurred during a crucial point? It would be bad and potentially very expensive.

FCC rules require in this case that a label with the name, call sign, and address of the licensee be affixed to the transmitter. Also, of course, make sure that you're operating it in bands where it is allowed.

Last edited by tfogarty. Register to edit

Tags: rules and regulations radio operation arrl chapter 6 arrl module 14

How might you obtain a list of active nodes that use VoIP?
  • From the FCC Rulebook
  • From your local emergency coordinator
  • Correct Answer
    From a repeater directory
  • From the local repeater frequency coordinator

The FCC rulebook provides guidelines for what is allowed, and local coordinators keep track of which repeaters are using which frequencies in which location in order to avoid interference between different nodes in the same area. None of those three sources would provide any definite information about what technologies or features a specific repeater has.

The best place to find information such as a list of active nodes that use VoIP is from an actively maintained repeater directory. A Repeater Directory is a list that someone (company, club, community, etc) maintains of repeaters that has information such as what features are on the repeater, who owns it, callsign, etc.

There are many repeater directories, both on paper and on the internet, such as here and here.

Last edited by bdengle32@yahoo.com. Register to edit

Tags: frequencies repeater arrl chapter 6 arrl module 13

How do you select a specific IRLP node when using a portable transceiver?
  • Choose a specific CTCSS tone
  • Choose the correct DSC tone
  • Access the repeater autopatch
  • Correct Answer
    Use the keypad to transmit the IRLP node ID

IRLP = Internet Radio Linking Project

**The aim of the IRLP is to link radio systems separated by long distance without the use of expensive leased lines, satellites, or controllers. IRLP uses Voice-Over-IP and the internet.

Using your handheld or mobile, you can access the system, and talk on simplex or repeater somewhere else in the world , i.e. Australia. This is a boon to those who like to work DX but are living in areas where they can not put up an HF station and antennae. Canadian Amateurs with their Basic qualification can work DX countries using IRLP. IRLP local nodes are on 2 metres, 70 cm, and 6 metres.

All YOU require is your radio, a DTMF keypad, (or outboard DTMF audio sending unit), and of course the access codes for the IRLP network. **

(Text copied from Kingston Amateur Radio Club website)


Last edited by bdengle32@yahoo.com. Register to edit

Tags: repeater arrl chapter 6 arrl module 13

What name is given to an amateur radio station that is used to connect other amateur stations to the Internet?
  • Correct Answer
    A gateway
  • A repeater
  • A digipeater
  • A beacon

In computer terms a gateway is the name of a device that connects two different networks together; a router is a type of gateway. Thus, a station that connects a packet radio network to the Internet is also a gateway.

A digipeater is a station that receives packets and then retransmits them; it's the only distractor that would make any sense, but it has nothing to do with the Internet, though it is possible for a digipeater to also be a gateway.

Repeaters simultaneously retransmit signals on another frequency and are used for voice operation; beacons transmit some form of information periodically. Neither has anything to do with packet radio.

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Tags: repeater digital modes arrl chapter 5 arrl module 11

What is meant by Voice Over Internet Protocol (VoIP) as used in amateur radio?
  • A set of rules specifying how to identify your station when linked over the Internet to another station
  • A set of guidelines for working DX during contests using Internet access
  • A technique for measuring the modulation quality of a transmitter using remote sites monitored via the Internet
  • Correct Answer
    A method of delivering voice communications over the Internet using digital techniques

Think of Voice Over Internet Protocol (VoIP) as Vonage or Skype. You're using the Internet to send the audio signal (voice) from a receiver (or a computer) to another radio or another computer for transmission through a radio

Last edited by y_ham. Register to edit

Tags: arrl chapter 6 arrl module 13

What is the Internet Radio Linking Project (IRLP)?
  • Correct Answer
    A technique to connect amateur radio systems, such as repeaters, via the Internet using Voice Over Internet Protocol
  • A system for providing access to websites via amateur radio
  • A system for informing amateurs in real time of the frequency of active DX stations
  • A technique for measuring signal strength of an amateur transmitter via the Internet

IRLP is one of several projects used for linking repeaters and other systems across the internet.

Amateurs use DTMF tones (phone keypad) on a radio to send control codes to the repeater to link or unlink with another repeater or node.

Similar technologies include EchoLink, AllStar, and Icom's D-Star network.

Last edited by kd7bbc. Register to edit

Tags: arrl chapter 6 arrl module 13

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