12. What type of neutralization does not rely on degenerative feedback to prevent
self-oscillation?
a. Link
c. Cross
b. Plate
d. Inductive
13. Interfering frequencies may be transmitted because of parasitic oscillations.
Sources of parasitic oscillations in a transmitter include
a. incorrect bias.
c. a defective fuse.
b. defective tubes.
d. degenerative feedback.
14. The purpose of inserting a parallel combination of resistor and coil into the
grid circuit of the final amplifier in a transmitter is to
a. aid grid-leak bias and make the amplifier operate class C.
b. broaden the bandwidth of the amplifier.
c. reduce parasitic oscillations.
d. eliminate harmonic distortion.
15. When inductive coupling is used in a transmitter, harmonic frequencies are
often transferred through electrostatic coupling.
What can you do to eliminate
this transfer of harmonics and still have a maximum transfer of desirable
frequencies?
a. Use a Faraday shield.
b. Space the inductors farther apart.
c. Space the inductors closer together.
d. Use high-power frequency multipliers.
16. Assume that an antenna presents a capacitive reactance to a transmitter. To
provide the maximum transfer of power from the transmitter to the antenna you would
a. increase inductance in the antenna coupling circuit.
b. decrease inductance in the antenna coupling circuit.
c. install a capacitor in parallel with the antenna.
d. detune the final RF amplifier.
17. When the antenna coupler of a transmitter is tuned to resonance, the load
that the antenna presents to the transmitter is
321 L3
16
Previous Page
