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18 Cards in this Set
- Front
- Back
3-57H1
The deviation ratio is the: |
Maximum carrier frequency deviation to the highest audio modulating frequency
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3-57H2
What is the deviation ratio for an FM phone signal having a maximum frequency deviation of plus or minus 5 kHz and accepting a maximum modulation rate of 3 kHz? |
1.66
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3-57H3
What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus or minus 7.5 kHz and accepting a maximum modulation rate of 3.5 kHz? |
2.14
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3-57H4
How can an FM-phone signal be produced in a transmitter? |
By feeding the audio directly to the oscillator
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3-57H5
What is meant by the term modulation index? |
The ratio between the deviation of a frequency modulated signal and the modulating frequency
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3-57H6
In an FM-phone signal, what is the term for the maximum deviation from the carrier frequency divided by the maximum audio modulating frequency? |
Deviation ratio
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3-58H1
In Figure 3H17, the block labeled 4 would indicate that this schematic is most likely a/an: |
SSB radio transmitter
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3-58H2
In Figure 3H17, which block diagram symbol (labeled 1 through 4) represents where audio intelligence is inserted? |
2
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3-58H3
What kind of input signal could be used to test the amplitude linearity of a single-sideband phone transmitter while viewing the output on an oscilloscope? |
A two-tone audio-frequency sine wave
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3-58H4
What does a two-tone test illustrate on an oscilloscope? |
Linearity of a SSB transmitter
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3-58H5
How can a double-sideband phone signal be produced? |
By modulating the supply voltage to a class C amplifier
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3-58H6
What type of signals are used to conduct an SSB two-tone test? |
Two non-harmonically related audio signals that are within the modulation band pass of the transmitter
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3-59H1
What is an important factor in pulse-code modulation using time-division multiplex? |
Synchronization of transmit and receive clock pulse rates
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3-59H2
In a pulse-width modulation system, what parameter does the modulating signal vary? |
Pulse duration
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3-59H3
What is the name of the type of modulation in which the modulating signal varies the duration of the transmitted pulse? |
Pulse-width modulation
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3-59H4
Which of the following best describes a pulse modulation system? |
The peak transmitter power is normally much greater than the average power
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3-59H5
In a pulse-position modulation system, what parameter does the modulating signal vary? |
The time at which each pulse occurs
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3-59H6
What is one way that voice is transmitted in a pulse-width modulation system? |
A standard pulse is varied in duration by an amount depending on the voice waveform at that instant
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