Abstract: A lightweight piezoelectric microphone using a metallized piezoelectric diaphragm arcuately bowed by a boss on a slotted baffle plate held in close parallel proximity to the diaphragm is disclosed. Slotted Helmholtz resonators provide frequency response shaping and wide band noise cancellation. Electrical contact between the diaphragm and an electrical conductor is provided by a conductive, elastic material compressed by parts of the microphone housing, into electrical contact with the conductor and a metallized side of the diaphragm.

Abstract: A strain relief clamp for supporting the signal cable dependent from a communications headset. A unitary, integrally molded plastic structure is provided having a pair of toothed jaws joined by a hingeless support member and lever actuated to effect a secure clamp action on the wearer's apparel. A pair of yieldable clamp arms with a cooperating clamp retainer ring are provided to adjustably position and secure the signal cable to the unitary strain relief clamp.

Abstract: A compact electro-acoustic transducer assembly is provided having a housing formed with an acoustic output socket extending longitudinally of the housing and at least one electro-acoustic transducer mounted on the housing in registration with the acoustic output socket. The housing is provided with an aperture for transmission of sound waves from the acoustic output of the transducer to the socket. Conductive leads are deposited on the surface of the housing for providing electrical connection between the transducer and a circuit board supporting the housing. The electrical input terminals to the transducer are surface mounted thereon for engagement against the conductive leads deposited on the housing. The transducer may be formed with a thin plate-like permanent magnet formed of a rare earth cobalt material and supported in a flux-retaining member.

Abstract: An acoustic headset having a pair of elongated channel structures for carrying sound tubes which are provided with ear pieces situated adjacent upper end regions of the channel structures. These channel structures have distant from their upper end regions, respectively, lower end regions interconnected with each other by way of a connecting structure which forms a continuous, elongated, one-piece body with the pair of channel structures. The connecting structure interconnects the pair of channel structures for movement toward and away from each other while a releasable holding structure is connected with the pair of channel structures for releasably holding them at a selected distance from each other, so that in this way it is possible for the ear pieces to be accommodated to the distance between the ears of a given individual.