Radio Receivers
The frequency generated by each decade in a direct frequency synthesizer is much higher than the frequency shown; this is done to

Reduce the spurious frequency problem
Increase the frequency stability of the synthesizer
Reduce the number of decades
Reduce the number of crystals required

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Radio Receivers
In a ratio detector

the output is twice that obtainable from a similar phase discriminator
stabilization against signal strength variations is provided
the circuit is the same as in a discriminator, except that the diodes are reversed
the linearity is worse than in phase discriminator

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Radio Receivers
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
The circuit is always biased in class C, by virtue of the leak-type bias.
Leak-type bias must be used

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Radio Receivers
In a radio receiver with simple AGC

The faster the AGC time constant the more accurate the output
An increase in signal strength produces more AGC
The audio stage gain is normally controlled by the AGC
The highest AGC voltage is produced

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