| 摘要 |
PURPOSE:To give warning to an external device only when charging is disable although a cordless handset 1 is set in a recessed part of a charging base. CONSTITUTION:When contacts a1, b1 and a2, b2 are electrically nonconductive regardless that a handset 1 is placed in a recessed part T of a charging base 6, an output of a conductivity detection circuit 15 goes to a low level, and as soon as an inverting output via an inverter 16, that is, a high level output is given to one input terminal of an AND circuit 17, a switch 10 is closed by the weight of the handset 1 to provide a high level output even to the other input terminal of the AND circuit 17, resulting that an AND output of the AND circuit 17 goes to a high level and an alarm buzzer 9 raises an alarm tone thereby raising the attention to the user. |
