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 number of crystals required Increase the frequency stability of the synthesizer Reduce the number of decades Reduce the spurious frequency problem Reduce the number of crystals required Increase the frequency stability of the synthesizer Reduce the number of decades Reduce the spurious frequency problem ANSWER DOWNLOAD EXAMIANS APP
Radio Receivers The local oscillator of a broadcast receiver is tuned to a frequency higher than the incoming frequency To help the image frequency rejection Because otherwise an intermediate frequency could not be produced To allow adequate frequency coverage without switching To permit easier tracking To help the image frequency rejection Because otherwise an intermediate frequency could not be produced To allow adequate frequency coverage without switching To permit easier tracking ANSWER DOWNLOAD EXAMIANS APP
Radio Receivers Three-point tracking is achieved with The padder capacitor Variable selectivity Double conversion Double spotting The padder capacitor Variable selectivity Double conversion Double spotting ANSWER DOWNLOAD EXAMIANS APP
Radio Receivers The typical squelch circuit cuts off An IF amplifier when the AGC is maximum RF interference when the signal is weak an audio amplifier when the carrier is absent An IF amplifier when the AGC is minimum An IF amplifier when the AGC is maximum RF interference when the signal is weak an audio amplifier when the carrier is absent An IF amplifier when the AGC is minimum ANSWER DOWNLOAD EXAMIANS APP
Radio Receivers In a ratio detector 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 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 ANSWER DOWNLOAD EXAMIANS APP
Radio Receivers In a radio receiver with simple AGC An increase in signal strength produces more AGC The highest AGC voltage is produced The faster the AGC time constant the more accurate the output The audio stage gain is normally controlled by the AGC An increase in signal strength produces more AGC The highest AGC voltage is produced The faster the AGC time constant the more accurate the output The audio stage gain is normally controlled by the AGC ANSWER DOWNLOAD EXAMIANS APP