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Figure 3H.—Gated-beam detector.
IN ANSWERING QUESTIONS 3-43
THROUGH 3-47, REFER TO FIGURE 3H.
3-43. What components in the circuit are used
to set the reference frequency for a gated-
beam detector?
1. C1 and L1
2. C2 and L2
3. C3 and L3
4. C4 and R1
3-44. What tube pins connect to elements that
perform in a manner similar to an AND
gate in a digital device?
1. Pins 1 and 3
2. Pins 3 and 4
3. Pins 3 and 5
4. Pins 4 and 5
3-45. What type of tank circuit is the
quadrature tank (L3 and C3)?
1. Low-Q
2. High-Q
3. Nonresonant
4. Series-resonant
3-46. For plate current to flow, what must be
the polarities of (a) the quadrature grid
and (b) the limiter grid?
1. (a) Negative
(b) negative
2. (a) Negative
(b) positive
3. (a) Positive
(b) positive
4. (a) Positive
(b) negative
3-47. ABOVE the center frequency of the
received fm signal, (a) will the tank
appear capacitive or inductive, and
(b) will the average plate current increase
or decrease?
1. (a) Inductive
(b) increase
2. (a) Inductive
(b) decrease
3. (a) Capacitive
(b) decrease
4. (a) Capacitive
(b) increase
3-48. To demodulate a phase-modulated signal,
which, if any, of the following types of
demodulators may be used?
1. Peak
2. Quadrature
3. Series-diode
4. None of the above
3-49. Which of the following circuits can be
used as a communications pulse
demodulator?
1. Conversion
2. Peak detector
3. Low-pass filter
4. Each of the above
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