Abstract: An interface device is provided for (1) automatically diagnosing the type and terminal connections of the earphone and microphone transducers used in any handset or headset and (2) automatically connecting any transducer set provided as a replacement handset or headset to emulate the original handset or headset. Subsequently, the user can connect, without further action, the replacement transducer set to the telephone base station.

Abstract: An immersion-resistant housing adapted to receive a vibratable diaphragm spanning the interior of the housing to divide the housing into first and second chambers includes a first port communicating between the first chamber and the exterior environment. The first port is configured as a tubulation. A second port communicates between the second chamber and the external environment. The tubulation has sufficiently small diameter that water entering therein moves essentially as a piston without breakup. The tubulation is configured to have a volume at least equal to that of the first chamber, and a hydrostatic head of about 32 feet of water is necessary before water can be forced into the first chamber. In the preferred embodiment the diaphragm completely seals the housing against direct communication between the two chambers.