| 摘要 |
PURPOSE:To attain selectively receiving of a caller without hooking off a handset at a called party by adding a calling detector, an emergency inquiring signal receiver, a remote party indicating signal transceiver, and an emergency indicating signal transceiver. CONSTITUTION:After the caller makes dialing, the caller depresses immediately remote party indicating button and an emergency indicating button. When the calling detector 1 is operated at the called party and a pseudo on-hook switch SW1 is closed, a switch SW2 is activated at the same time and an emergency inquiry signal transmitter 2S returns an Sa signal to the caller. The caller receives the Sa signal, activates a switch SW3, and transmits a remote party indicating signal Sb and an emergency indicating signal Sc. A receiver 3R of the caller receives this signal, and a controller lights a remote party indicating display so as to inform the emergency to the remote party. |
