Abstract: Coupling apparatus for a telephone handset comprises a handset-coupling cradle having a dome at one end thereof for locating the earpiece (receiver) of the handset, and sound ports at the other end of the cradle in the region where the mouthpiece (microphone) of the handset resides. The handset-coupling cradle is shaped to accommodate a variety of different handset styles. An inductive sensor is mounted within the dome and it responds to electromagnetic fields generated by the handset receiver. Such a sensor eliminates the need to closely couple the receiver to the apparatus. A low acoustic impedance loudspeaker is mounted beneath the sound ports for acoustically coupling signals to the handset's microphone. Such a loudspeaker eliminates the need to closely couple the microphone to the apparatus.

Abstract: A directional microphone assembly is constructed from a first-order-gradient microphone element enclosed within a housing, molded from an acoustically-opaque, resilient material such as Ethylene-Propylene-Diene-Monomer. The microphone element includes a diaphragm which moves under the influence of sound pressures applied on its opposite surfaces to generate an electrical signal which is proportional to the differential sound pressure. The housing includes a first acoustically-transparent channel for communicating sound pressure from a first opening in the housing to one surface of the diaphragm, and a second acoustically-transparent channel for communicating sound pressure from a second opening in the housing to the other surface of the diaphragm. The housing supports the microphone element and forms a continuous seal around its perimeter so that sound pressure in one channel does not leak into the other.