DEVICE DECREASING AUTOMATICALLY SOUND OF TELEVISION RECEIVER OR STEREO EQUIPMENT WHILE USING TELEPHONE SET

摘要

PURPOSE:To attain talking without being disturbed by sound from a television set or the like by providing a circuit decreasing a current given to a speaker through the hook-off of a handset. CONSTITUTION:With a telephone set not in use, a switch A is closed and a current from a circuit C is given to a speaker in the normal state via the switch A and a circuit D. On the other hand, when the handset is hooked off, the switch A is turned off and the current from the circuit C flows through a semi- fixed resistor B and the sound from the speaker is decreased.