c.
compresses the modulated signal into a narrower bandwidth.
d.
expands the modulated signal into a spread-spectrum signal.
11.
The stage that removes the undesired harmonics from the signal to be transmitted is the
a.
attenuator.
c.
harmonic filter.
b.
harmonic mixer.
d.
reverse directional coupler.
12.
The function of the reverse-directional coupler and the reflected power switch is to remove
a.
excess power from the RF system.
b.
the RF drive from the klystron when an arc is detected in the RF system.
c.
the RF drive from the klystron when the voltage standing-wave ratio exceeds the critical value.
d.
a portion of the transmitted signal so that a locking signal can be developed to lock the klystron.
13.
What is the disadvantage of using only one mixing stage in the translator subsystem?
a.
Bandwidth of the final signal is too wide.
b.
It is difficult to suppress unwanted signals.
c.
Power levels of the modulated signals are too low.
d.
It is difficult to generate the final frequency by only one oscillator.
14.
The stages used as the exciter in a ground station transmitter generally contain a traveling-wave tube,
attenuators, filters, and directional couplers. The purpose of the exciter is to raise the power level of the
a.
baseband signal prior to modulation.
b.
injection voltage prior to modulation.
c.
modulated signal prior to final amplification.
d.
modulated signal prior to mixing with the injection voltage.
15.
The purpose of the heat exchanger unit in the microwave transmitter is to cool the
a.
translator.
c.
modulation amplifier.
b.
attenuators.
d.
high-power amplifier.
344 L3
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