1. By changing the frequency of the incoming signal to a frequency of fixed
value, the radio receiver provides maximum
a. stability, selectivity, and sensitivity.
b. stability, sensitivity, and fidelity.
c. fidelity, selectivity, and stability.
d. sensitivity, fidelity, and selectivity.
2. Assume that the mixer stage of a radio receiver is fed an input frequency of
7,100 kHz and a local oscillator frequency of 7,130 kHz.
What is the beat
frequency generated by the mixer?
a. 30 Hz
c. 3 kHz
b. 300 Hz
d. 30 kHz
3. The intermediate frequency selected for a radio receiver is usually well
above the highest AF component in the desired signal because the
a. oscillator is more stable at higher frequencies.
b. heterodyne action is more efficient at higher frequencies.
c. possibility of distorting the desired signal is reduced.
d. higher frequencies are more easily amplified.
4. Assume that two alternating currents differing in frequency are applied to a
linear device such as a resistor. The voltages appearing across the resistor will
contain what frequencies?
a. Frequencies twice the value of the applied frequencies
b. The original frequencies of the applied alternating currents
c. A frequency equal to the sum of the original applied frequencies
d. A frequency equal to the difference of the two applied frequencies
5. The selectivity of a radio receiver is improved by
a. increasing the percentage of frequency separation without changing the
numerical frequency separation.
b. amplification of the signal at high fixed frequencies.
c. the use of resistance-capacitance coupling systems.
d. the use of diode detectors.
322 L1
3
Previous Page
