Abstract: A method and apparatus for improving the propagation of magnetic fields by electrodynamic/magnetic transducers, particularly in telecommunication devices, such that static magnetic fields produced by the transducers are substantially shielded and dynamic magnetic fields are radiated in a substantially unimpeded manner, a magnetic cover which is substantially impermeable to static magnetic fields from an electrodynamic/magnetic transducer is used at least in the sound exit region of the transducer.

Abstract: A handset for a telephone station composed of an upper shell and a lower shell in which a telephone receiver and transmission capsule are arranged. The telephone receiver and transmission capsule are contacted to the lines of the handset connecting cable via insulation displacement contacts provided at them. The transmission capsule is designed so that it optimally meets acoustical requirements, ease of assembly and matching to various designs made of it. The transmission capsule is formed by an electret microphone attached on a separate holder. The holder is designed such that it can be employed in various handset types and can be matched to the respectively required antechamber volume of the handset.

Abstract: An electro-acoustic transducer having a circular transducer plate arranged in a transducer housing, clamped between two mounting members at its edge region, is provided with a piezoelectric layer. At least one seating region of the mounting member is of a rotationally asymmetrical shape to attenuate partial oscillations of a higher order. The electro-acoustic transducer is usable as a transducer for telephones.