RADIO RECEIVERS QUIZ

Indicate which of the following circuits could not demodulate SSB:

Phase discriminator

Balance modulator

Product modulator

BFO

TRUE ANSWER : ?
YOUR ANSWER : ?

Show which of the following statements about the amplitude limiter is untrue:

When the input increases past the threshold of the limiting, the gain decreases to keep the output constant.

The output must be tuned

Leak-type bias must be used

The circuit is always biased in class C, by virtue of the leak-type bias.

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YOUR ANSWER : ?

To prevent overloading of the IF amplifier in a receiver, one should use

Squelch

Variable selectivity

Double conversion

Variable sensitivity

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YOUR ANSWER : ?

If the intermediate frequency is very high (indicate false statement)

Image frequency rejection is very good

The local oscillator need not be extremely stable

Tracking will be improved

The selectivity will be poor

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YOUR ANSWER : ?

A superheterodyne receiver with an IF of 450 kHz is tuned to a signal at 1200 kHz. The image frequency is

900 kHz

1650 kHz

2100 kHz

750 kHz

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YOUR ANSWER : ?

Indicate which of the following statements about the advantages of the phase discriminator over the slope detector is false:

Greater limiting

Fewer tuned circuits

Much easier alignment

Better linearity

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YOUR ANSWER : ?

The typical squelch circuit cuts off

an audio amplifier when the carrier is absent

RF interference when the signal is weak

An IF amplifier when the AGC is minimum

An IF amplifier when the AGC is maximum

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YOUR ANSWER : ?

In a ratio detector

the linearity is worse than in phase discriminator

the output is twice that obtainable from a similar phase discriminator

the circuit is the same as in a discriminator, except that the diodes are reversed

stabilization against signal strength variations is provided

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YOUR ANSWER : ?

A low ratio of the ac to the dc load impedance of a diode detector results in

Poor AGC operation

Diagonal clipping

Negative-peak clipping

Poor AF response

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YOUR ANSWER : ?

The local oscillator of a broadcast receiver is tuned to a frequency higher than the incoming frequency

Because otherwise an intermediate frequency could not be produced

To permit easier tracking

To allow adequate frequency coverage without switching

To help the image frequency rejection

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YOUR ANSWER : ?