Device for detecting operation state of telephone hook switch

摘要

A device for detecting an operation state of a telephone hook switch in a telephone includes a timer, a controlling circuit, a counter and a table electrically interconnected. According to the present invention, the abnormal signals generated by the hook switch cannot be accepted by an exchange or even if the signals are accepted by the exchanger, the mute function of the telephone will be utilized to make the users unable to listen to each other.