| 摘要 |
PURPOSE:To easily select an input source by a simple connection, by transmitting an operation start signal through a connecting code between an operation start signal generating circuit provided on an acoustic soure apparatus and an amplifier, to the amplifier from said circuit, and selecting the acoustic source apparatus. CONSTITUTION:Among 3 switchs of an input source selecting and switching circuit 24, which have been provided so as to corrspond to a tuner, a player 3 and a tape deck, for instance, when a tone arm is detached from a supporting base in order to use the player 3 in case when the switch of the tape deck is on, a switch 13 is turned off, the charge with which a capacitor C1 has been charged flows to a resistance R7 through a capacitor C2 and a diode D1, and a positive pulse is outputted from an output terminal 3a. This pulse is inputted to an input terminal 3b of an amplifier 5 through a signal cord 8, and is inputted to an input switching driving circuit 23 from a receiving circuit 22 through an equalizing circuit 25 and a capacitor C22. In this way, terminals 33, 35 are connected, and a sound whose input source is the player 3 from the equalizing circuit 25 is outputted from a loudspeaker 6. |
