14. Compared with the ratio detector, the phase discriminator has the advantage
of
a. having greater response to AM.
b. requiring no limiter stage.
c. having greater sensitivity.
d. being easier to align.
15. In selecting a demodulating circuit for an FM receiver, the type that is
recommended to provide the greatest discrimination against cochannel (signals
within the same channel) interference is the
a. ratio detector.
b. phase discriminator.
c. cycle-counting detector.
d. locked-oscillator detector.
16. The type of FM demodulating circuit that has the simplest alignment procedure
is the
a. locked-oscillator detector.
b. gated-beam-tube detector.
c. cycle-counting detector.
d. ratio detector.
17. Good bias stability is one of the requirements that must be fulfilled in IF
amplifier circuits to obtain the desired sensitivity.
One method used to obtain
the needed stability is to
a. overcouple the IF transformers.
b. use resistors to load the tuned circuits.
c. ground the base leads and use separate power supplies for the emitters and
collectors.
d. install
common-emitter
configurations
and
incorporate
neutralizing
circuits.
18. Resistive loading of the tuned circuits of IF stages tends to increase the
a. sensitivity of the amplifiers to temperature changes.
b. possibility of amplifier oscillation.
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