key word: INCREASE. An amplifier reproduces its input signal into a larger output signal ( more voltage, more current, more power).
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If an amplifier is 'linear', amplification, as a ratio of output versus input, will be constant regardless of frequency or amplitude of the input signal. Linearity is synonym with 'absence of distortion'. 'Non-linear' implies distortion.
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key words: INCREASE WEAK microphone signal. An 'audio amplifier'. Frequently called a 'speech amplifier' or 'microphone amplifier' for this particular application.
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Frequencies audible to humans range from 20 Hz to 20 000 Hz. Speech frequencies important for intelligibility in communications range from 300 Hz to 3000 Hz.
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Gain (synonymous with amplification) is an increase in signal voltage/current/power. 'Attenuation' is a loss (opposite to gain). 'Amplitude' is the instantaneous value of a signal. 'Modulation' is the impression of a message onto another signal.
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Gain and Amplification are synonymous. 'Attenuation' is a loss (opposite to gain). 'Oscillation' is the production of an Alternating Current (AC) signal. 'Modulation' is the impression of a message onto another signal.
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Gain and Amplification are synonymous. 'Attenuation' is a loss (opposite to gain). 'Oscillation' is the production of an Alternating Current (AC) signal. 'Modulation' is the impression of a message onto another signal.
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Recall that Inductance, a property of coils, is influenced by "The core material, the core diameter, the length of the coil and the number of turns of wire used to wind the coil".
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key word: NOT. Gain and Amplification are synonymous. Linearity (or lack of distortion) is a specification of amplifiers. Loss has nothing to do with amplifiers.
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Changing AC to DC is called 'Rectification'. AC is turned into 'pulsating DC' (it flows in one direction only) after going through a diode. In Power Supply circuits, diodes are called 'Rectifiers'. Diodes have two electrodes: Cathode and Anode. Electrons flow from Cathode to Anode in a forward-biased (i.e., a diode subjected to a voltage polarity which permits conduction) diode.
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A DIODE, vacuum tube or semiconductor, has two electrodes: Anode and Cathode. Electrons flow from Cathode to Anode in a forward-biased (i.e., a diode subjected to a voltage polarity which permits conduction) diode. Cathode/Grid/Anode(plate) are electrodes in a vacuum triode. Source/Gate/Drain are electrodes in a Field Effect Transistor (FET, N-Channel or P-Channel). Emitter/Base/Collector are electrodes in a Bipolar Transistor ( type PNP or NPN ).
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Changing AC to DC is called 'Rectification'. AC is turned into 'pulsating DC' (it flows in one direction only) after going through a diode. In Power Supply circuits, diodes are called 'Rectifiers'. Diodes have two electrodes: Cathode and Anode. Electrons flow from Cathode to Anode in a forward-biased (i.e., a diode subjected to a voltage polarity which permits conduction) diode.
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A DIODE, vacuum tube or semiconductor, has two electrodes: Anode and Cathode. Electrons flow from Cathode to Anode in a forward-biased (i.e., a diode subjected to a voltage polarity which permits conduction) diode. Cathode/Grid/Anode(plate) are electrodes in a vacuum triode. Source/Gate/Drain are electrodes in a Field Effect Transistor (FET, N-Channel or P-Channel). Emitter/Base/Collector are electrodes in a Bipolar Transistor ( type PNP or NPN ).
Original copyright; explanations transcribed with permission from Francois VE2AAY, author of the ExHAMiner exam simulator. Do not copy without his permission.
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A DIODE, vacuum tube or semiconductor, has two electrodes: Anode and Cathode. Electrons flow from Cathode to Anode in a forward-biased (i.e., a diode subjected to a voltage polarity which permits conduction) diode. Cathode/Grid/Anode(plate) are electrodes in a vacuum triode. Source/Gate/Drain are electrodes in a Field Effect Transistor (FET, N-Channel or P-Channel). Emitter/Base/Collector are electrodes in a Bipolar Transistor ( type PNP or NPN ).
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key words: AMPLIFY, LOW VOLTAGE. A transistor amplifies signals and can work at a low voltage. Bipolar Transistors ( type PNP or NPN ) as well as Field Effect Transistor (FET, N-Channel or P-Channel) can amplify signals.
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key words: SEMICONDUCTOR, AMPLIFY. A transistor amplifies signals. Bipolar Transistors ( type PNP or NPN ) as well as Field Effect Transistor (FET, N-Channel or P-Channel) can amplify signals. A 'single P-N junction' is a diode. Diodes have two main uses: 'Rectification' and 'Detection'.
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Emitter/Base/Collector are electrodes in a Bipolar Transistor ( type PNP or NPN ). Source/Gate/Drain are electrodes in a Field Effect Transistor (FET, N-Channel or P-Channel). Cathode/Grid/Anode(plate) are electrodes in a vacuum triode.
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Detection = DEmodulation = Recovery of the message carried on a radio signal. 'Modulation' is the impression of a message onto another signal. 'Rectification' turns AC into 'pulsating DC' (it flows in one direction only) after going through a diode.
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Emitter/Base/Collector are electrodes in a Bipolar Transistor ( type PNP or NPN ). Source/Gate/Drain are electrodes in a Field Effect Transistor (FET, N-Channel or P-Channel). Cathode/Grid/Anode(plate) are electrodes in a vacuum triode.
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key word: NPN. The only choice in the group comprising a sandwich of N-semiconductor and P-semiconductor is the 'Bipolar Transistor'.
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Comparing Triode/Bipolar Transistor/FET in terms of their RESPECTIVE electrodes: Origin of charge carriers = Cathode/Emitter/Source. Control electrode = Grid/Base/Gate. Destination of charge carriers = Anode(plate)/Collector/Drain.
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Comparing Triode/Bipolar Transistor/FET in terms of their RESPECTIVE electrodes: Origin of charge carriers = Cathode/Emitter/Source. Control electrode = Grid/Base/Gate. Destination of charge carriers = Anode(plate)/Collector/Drain.
Original copyright; explanations transcribed with permission from Francois VE2AAY, author of the ExHAMiner exam simulator. Do not copy without his permission.
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Comparing Triode/Bipolar Transistor/FET in terms of their RESPECTIVE electrodes: Origin of charge carriers = Cathode/Emitter/Source. Control electrode = Grid/Base/Gate. Destination of charge carriers = Anode(plate)/Collector/Drain.
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In a field effect transistor, Source and Drain are the two extremities of a 'channel' made of a single semi-conductor type. NPN and PNP are the two types of BIPOLAR Transistors.
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Source/Gate/Drain are electrodes in a Field Effect Transistor (FET, N-Channel or P-Channel). Emitter/Base/Collector are electrodes in a Bipolar Transistor ( type PNP or NPN ). Cathode/Grid/Anode(plate) are electrodes in a vacuum triode.
Original copyright; explanations transcribed with permission from Francois VE2AAY, author of the ExHAMiner exam simulator. Do not copy without his permission.
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Comparing Triode/Bipolar Transistor/FET in terms of their RESPECTIVE electrodes: Origin of charge carriers = Cathode/Emitter/Source. Control electrode = Grid/Base/Gate. Destination of charge carriers = Anode(plate)/Collector/Drain.
Original copyright; explanations transcribed with permission from Francois VE2AAY, author of the ExHAMiner exam simulator. Do not copy without his permission.
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Comparing Triode/Bipolar Transistor/FET in terms of their RESPECTIVE electrodes: Origin of charge carriers = Cathode/Emitter/Source. Control electrode = Grid/Base/Gate. Destination of charge carriers = Anode(plate)/Collector/Drain.
Original copyright; explanations transcribed with permission from Francois VE2AAY, author of the ExHAMiner exam simulator. Do not copy without his permission.
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Comparing Triode/Bipolar Transistor/FET in terms of their RESPECTIVE electrodes: Origin of charge carriers = Cathode/Emitter/Source. Control electrode = Grid/Base/Gate. Destination of charge carriers = Anode(plate)/Collector/Drain.
Original copyright; explanations transcribed with permission from Francois VE2AAY, author of the ExHAMiner exam simulator. Do not copy without his permission.
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Comparing Triode/Bipolar Transistor/FET in terms of their RESPECTIVE electrodes: Origin of charge carriers = Cathode/Emitter/Source. Control electrode = Grid/Base/Gate. Destination of charge carriers = Anode(plate)/Collector/Drain.
Original copyright; explanations transcribed with permission from Francois VE2AAY, author of the ExHAMiner exam simulator. Do not copy without his permission.
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Comparing Triode/Bipolar Transistor/FET in terms of their RESPECTIVE electrodes: Origin of charge carriers = Cathode/Emitter/Source. Control electrode = Grid/Base/Gate. Destination of charge carriers = Anode(plate)/Collector/Drain.
Original copyright; explanations transcribed with permission from Francois VE2AAY, author of the ExHAMiner exam simulator. Do not copy without his permission.
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Comparing Triode/Bipolar Transistor/FET in terms of their RESPECTIVE electrodes: Origin of charge carriers = Cathode/Emitter/Source. Control electrode = Grid/Base/Gate. Destination of charge carriers = Anode(plate)/Collector/Drain.
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Source and Drain are the two ends of the same block of semiconductor material, the 'Channel'. Only the control electrode, the Gate, is made of the opposite type of material.
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Vacuum triodes are larger, use current just to heat the filament and require higher voltages than transistors BUT they remain simpler to use in HIGH-POWER amplifiers.
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key words: AMPLIFY, HIGH VOLTAGE. Vacuum tubes amplify signals but work at higher voltages than transistors (generally low-voltage devices).
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The 'Plate' (or Anode) attracts electrons with a high positive voltage. The Cathode emits electrons. The Grid encircles the Cathode and controls the flow of electrons.
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The 'Grid' is a wire mesh (looking like a fence, so to speak) around the Cathode. The 'Plate' (or Anode) attracts electrons with a high positive voltage. The Cathode emits electrons. The Grid encircles the Cathode and controls the flow of electrons.
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key words: ELEMENT, FURTHEST. A "directly-heated triode" comprises a filament (serving as a cathode, emitting electrons), a grid and a plate (or anode). An "indirectly-heated triode" comprises a heater (heating the cathode), a cathode (emitting electrons), a grid and a plate (or anode).
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The 'Plate' (or Anode) attracts electrons with a high positive voltage. The Cathode emits electrons. The Grid encircles the Cathode and controls the flow of electrons.
Original copyright; explanations transcribed with permission from Francois VE2AAY, author of the ExHAMiner exam simulator. Do not copy without his permission.
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