8. Assume that the plate power input to the power amplifier of a low-level AM
transmitter is 225 watts and the output power is 55 watts.
In an FM transmitter
which is also low-level modulated the power amplifier with the same power input is
capable of producing a maximum power output of
a. 45 to 90 watts.
b. 90 to 135 watts.
c. 135 to 180 watts.
d. 180 to 225 watts.
b. decreasing the grid excitation.
c. increasing the Q of the tank circuit.
d. inserting an adjustable capacitor between the plate and grid.
10. A comparison of the single-ended amplifier shown in figure 72 of TM 11-668
and the push-pull amplifier shown in A of figure 74 reveals that the input and
output capacitances across the tank circuits of the push-pull circuit are one half
those in the single-ended circuit.
Since the output voltage of the push-pull
circuit is twice that of the single-ended circuit, what is the relationship between
a. Z's of the two circuits are equal.
b. Z of the push-pull circuit is twice that of the single ended.
c. Z of the single-ended circuit is twice that of the push-pull.
d. Z of the push-pull circuit is four times that of the single ended.
11. A circuit that permits a triode to be operated as a power amplifier at high
a. grid-cathode input, plate-cathode output, and grounded cathode.
b. grid-ground input, cathode-ground output, and grounded plate.
c. cathode-ground input, plate-ground output, and grounded grid.
d. grid-cathode input, plate-ground input, and grounded grid.
12. The grid-tank circuit that would be most appropriate for use in a power
amplifier located several feet from the driver is shown in TM 11-668, figure 75,