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

To permit easier tracking
To allow adequate frequency coverage without switching
Because otherwise an intermediate frequency could not be produced
To help the image frequency rejection

ANSWER DOWNLOAD EXAMIANS APP

Radio Receivers
In a ratio detector

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

ANSWER DOWNLOAD EXAMIANS APP

Radio Receivers
In a broadcast superheterodyne receiver, the

RF amplifier normally works at 455 kHz above the carrier frequency
Mixer input must be tuned to the signal frequency
Local oscillator operates below the signal frequency
Local oscillator frequency is normally double the IF

ANSWER DOWNLOAD EXAMIANS APP