Telephone hand switch for inhibiting sound transmission - permits subscriber to allow and inhibit transmission whilst listening using the hand holding the handpiece

摘要

The simple switch element is for incorporating in the handpiece of a normal telephone, which allows the user to inhibit and permit transmission at will. The switch is so situated and shaped that it can be operated by the hand holding the handpiece, so that the other hand can continue writing. Basically the device consists of a sliding button, which is operated by the user, attached to a small flat insulating plate by means of a rod, all mounted inside the handpiece. The flat plate is pushed between the contacts of a circuit breaker incorporated in the circuit which actuates the microphone. In one position the plate deactivates this circuit, while in the other position normal operation is possible. Two slightly different forms of the actual switching arrangement are presented and mention is also made of the possibility of having a cruciform shaped turning switch to "lock" the device into one mode.