Receiver

Abstract

Abstract PURPOSE: To favorably display a C/N by obtaining a display signal for a carrier- to-noise ratio (C/N) by using a sound subcarrier wave, and displaying it. CONSTITUTION: A first intermediate frequency signal SIF 1 is inputted to an indoor unit 17, and is converted into a second intermediate frequency signal SIF 2 by a mixer 19 through a first intermediate frequency amplifier 18, and is demodulated by an FM demodulator 25 through an amplifier 23 and an AGC 24. An FM signal SATM from the demodulator 25 is demodulated by an FM demodulator 29 through a sub-carrier wave BPF 28, and a sound signal SA is outputted through a sound signal processing circuit 30. The output signal of the FM demodulator 29 is displayed on a display unit 5 through the BPF l with a passband outside the band of the sound signal, the amplifier 2, a rectifier 3 and the amplifier 4. Then, since the BPF 1 has the passband outside the band of the sound signal, the output signal of it is a part of a triangular noise, caused by the FM demodulator 29, and this noise level is determined by the C/N of the FM sound signal SAFM, supplied to the demodulator 29. COPYRIGHT: (C)1989,JPO&Japio

Inventors

• 👤 Yukio Shinei

Bibliographic Details