| 摘要 |
PURPOSE:To provide extremely-useful manipulation by making it possible to control the sound volume of a sound multiplex adapter by the variable volume knob of a receiver or a remote control transmitter. CONSTITUTION:With compound switch 17 of the sound multiplex adaptor ON, a sound multiplex outputted from sound output circuit 11 of the TV receiver is inputted to multiplex demodulation circuit 18, where a main sound signal and subsound signal are obtained as its output. With switch 17 OFF, the power supply of adaptor 13 is turned OFF and the multiplex signal output is returned to circuit 11 of receiver 8 via switch 17 while only the main sound signal is outputted to speaker 12. Although electronic volume unit 19 attenuates both main and subsound signals, this attenuation is controlled by the output of remote control receiver 9 or volume unit 10 and the input voltage to sound output circuit 20 is also controlled in consequence, so that the volume will be controlled. |
