Key Topic 58: SSB Modulation

Question 1

3-58H1: In Figure 3H17, the block labeled 4 would indicate that this schematic is most likely a/an:

A. Audio amplifier.
B. Shipboard RADAR.
C. SSB radio transmitter.
D. Wireless LAN (local area network) computer

Answer 1

C. SSB radio transmitter.

Question 2

3-58H2: In figure 3H17, which block diagram symbol (labeled 1 through 4) represents where audio intelligence is inserted?

A. 1
B. 2
C. 3
D. 4

Answer 2

B. 2

Question 3

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. Whistling in the microphone.
B. An audio frequency sine wave.
C. A two-tone audio-frequency sine wave.
D. An audio frequency square wave.

Answer 3

C. A two-tone audio-frequency sine wave.

Question 4

3-58H4: What does a two-tone test illustrate on an oscilloscope?

A. Linearity of a SSB transmitter.
B. Frequency of the carrier phase shift.
C. Percentage of frequency modulation.
D. Sideband suppression.

Answer 4

A. Linearity of a SSB transmitter.

Question 5

3-58H5: How can a double-sideband phone signal be produced?

A. By using a reactance modulator.
B. By varying the voltage to the varactor in an oscillator circuit.
C. By using a phase detector, oscillator, and filter in a feedback loop.
D. By modulating the supply voltage to a class C amplifier.

Answer 5

D. By modulating the supply voltage to a class C amplifier.

Question 6

3-58H6: What type of signals are used to conduct an SSB two-tone test?

A. Two audio signals fo the same frequency, but shifted 90 degrees in phase.
B. Two non-harmonically related audio signals that are within the modulation band pass of the transmitter.
C. Two different audio frequency square wave signals of equal amplitude.
D. Any two audio frequencies as long as they are harmonically related.

Answer 6

B. Two non-harmonically related audio signals that are within the modulation band pass of the transmitter.