Radio Receivers In a broadcast superheterodyne receiver, the Local oscillator frequency is normally double the IF Local oscillator operates below the signal frequency Mixer input must be tuned to the signal frequency RF amplifier normally works at 455 kHz above the carrier frequency Local oscillator frequency is normally double the IF Local oscillator operates below the signal frequency Mixer input must be tuned to the signal frequency RF amplifier normally works at 455 kHz above the carrier frequency ANSWER DOWNLOAD EXAMIANS APP
Radio Receivers The typical squelch circuit cuts off An IF amplifier when the AGC is minimum RF interference when the signal is weak an audio amplifier when the carrier is absent An IF amplifier when the AGC is maximum An IF amplifier when the AGC is minimum RF interference when the signal is weak an audio amplifier when the carrier is absent An IF amplifier when the AGC is maximum ANSWER DOWNLOAD EXAMIANS APP
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 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 ANSWER DOWNLOAD EXAMIANS APP
Radio Receivers To prevent overloading of the IF amplifier in a receiver, one should use Double conversion Variable selectivity Squelch Variable sensitivity Double conversion Variable selectivity Squelch Variable sensitivity ANSWER DOWNLOAD EXAMIANS APP
Radio Receivers If the intermediate frequency is very high (indicate false statement) Image frequency rejection is very good Tracking will be improved The local oscillator need not be extremely stable The selectivity will be poor Image frequency rejection is very good Tracking will be improved The local oscillator need not be extremely stable The selectivity will be poor ANSWER DOWNLOAD EXAMIANS APP
Radio Receivers A low ratio of the ac to the dc load impedance of a diode detector results in Poor AGC operation Negative-peak clipping Poor AF response Diagonal clipping Poor AGC operation Negative-peak clipping Poor AF response Diagonal clipping ANSWER DOWNLOAD EXAMIANS APP
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