11
2-9. Fsk has which of the following advantages
over cw?
1. Fsk has a more stable oscillator
2. Fsk is easier to generate
3. Fsk rejects unwanted weak signals
4. Fsk does not have noise in its output
2-10. The "ratio of transmitted powers" provides
what information?
1. Transmitter power out in a cw system
2. Transmitter power out in an fsk system
3. Improvement shown using cw instead
of fsk transmission
4. Improvement shown using fsk instead
of cw transmission methods
2-11. In an fm signal, (a) the RATE of shift is
proportional to what characteristic of the
modulating signal, and (b) the AMOUNT
of shift is proportional to what
characteristic?
1. (a) Amplitude
(b) amplitude
2. (a) Amplitude
(b) frequency
3. (a) Frequency
(b) frequency
4. (a) Frequency
(b) amplitude
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INTENTIONALLY.
Figure 2A.—Oscillator circuit.
IN ANSWERING QUESTIONS 2-12
THROUGH 2-14, REFER TO FIGURE 2A.
2-12. When a sound wave strikes the condenser
microphone (M), it has which, if any, of
the following effects on the oscillator
circuit?
1. It changes output phase
2. It changes output voltage
3. It changes output frequency
4. It has no effect
2-13. What is the purpose of capacitor C in the
circuit?
1. It helps set the carrier frequency of the
oscillator
2. It prevents amplitude variations in the
oscillator output
3. It sets the maximum frequency
deviation of the oscillator
4. It varies the output frequency in
accordance with the modulating
voltage
