FREQUENCY CONVERTING CIRCUIT, DEMODULATING CIRCUIT AND TV RECEIVER

摘要

PROBLEM TO BE SOLVED: To provide a demodulating circuit where a Nyquist buzz is not caused. SOLUTION: First and second multipliers 31 and 32 multiply an IF signal outputted from a band-pass filter 16 respectively by a carrier wave reproduced by a carrier wave reproducing part 7 and a carrier wave which is deviated in phase by π/2 from the carrier wave. Then the products are respectively multiplied by themselves through the use of first and second square circuits 33 and 34 and, then, added by an adder 35. An error owing to a Nyquist slope is erased from the output of the adder 35.