3. Assume that the unloaded Q of the power amplifier (V9) tank circuit is 180,
and the loaded Q is 9.
The transfer efficiency of the tank circuit is
a. 75 percent.
b. 85 percent.
4. After changing V5 to a quadrupler to eliminate the first doubler, it is found
that parasitic oscillations occur. These parasitics can be suppressed by inserting
a. parallel-tuned trap in the screen grid lead.
c. small high-frequency capacitor between pins 3 and 5 of V5.
d. small resistor in the lead between pin 5 of V5 and pin 1 of transformer
5. Analysis of the transmitter circuit shows that the coupling circuit between
a. inductive with link coupling.
c. capacitive with the control grid at RF ground.
d. inductive with tuned primary and untuned secondary.
6. Assume that a given portable, direct FM transmitter contains a 20.850-MHz
oscillator, a frequency doubler, and a power amplifier.
If the frequency of the
oscillator swings between the limits of 20.848 MHz and 20.852 MHz while being
modulated, the frequency deviation of the transmitter is
a. 2 kHz.
b. 4 kHz.
7. Analysis of the ib - ec curve for a given electron tube shows that the grid
tube is to be used as a doubler in an FM transmitter, its operating bias must be
adjusted to approximately
a. -20 volts.
b. -8 volts.