11. In the diode detector circuit shown in figure 190 of TM 11-665, the carrier
is separated from the audio signal because one circuit element offers low
opposition to intermediate frequencies and high opposition to audio frequencies.
The circuit element that is used for this purpose is
a. C.
c.
Cc.
b. CO.
d.
R.
12. Radio reception is greatly improved by the use of the AVC circuit.
This
circuit is used in a communication receiver to
a. vary the output volume of the receiver automatically when the signal input
changes.
b. counteract the effects of fading by keeping the output volume relatively
constant.
c. change the bias of sharp cutoff tubes to control the amplification.
d. increase the sensitivity of the receiver.
13. To develop a smooth AVC voltage in a superheterodyne receiver, the modulated
signal is rectified and filtered to separate the RF and AF components. The stage
in which the AVC voltage is developed is the
a. detector.
c. RF amplifier.
b. converter.
d. IF amplifier.
14. One method of muting a communication receiver and eliminating reception of
noise when a station is not being received, is to apply a squelch or quiet AVC bias
voltage to
a. a triode or pentode tube for development of a cutoff bias for the first
detector stage.
b. a control tube for creation of a blocking bias for the AF amplifier.
c. the grid of the diode detector.
d. Rf and IF stages.
15. A transistorized radio communication receiver normally
uses
more
IF
amplifiers than a comparable electron-tube receiver because the
a. transformers in the transistorized receivers are replaced by capacitive-
coupled circuits.
b. transistorized IF amplifiers never use double-tuned transformers.
322 L3
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