摘要 |
<p>A control circuit (10) for an electrical telephone accessory (13) detects if the telephone receiver is on the cradle, the telephone ringer is actuated, or if the telephone receiver is lifted from the cradle. The control circuit (10) connects the electrical telephone accessory (13) to a power supply source when the telephone ringer is actuated or when the telephone receiver is lifted from the cradle. <IMAGE></p> |