Abstract: An electroacoustic transducer of the electret type, having a backplate situated above a diaphragm, with the backplate being provided with spacers. The diaphragm is clamped on a frame-shaped carrier located at an underside of the diaphragm. The carrier is provided with supporting portions which are vertically aligned with the spacers. In one embodiment, supporting posts are formed on the supporting portions to allow the carrier to rest on a case bottom. The resulting electroacoustic transducer can be easily assembled with a reduced risk of damage.

Abstract: Optical receiving system, incoming unipolar pulses being converted into bipolar pulses having a constant top amplitude (elements 2, 3 and 4) which, on the one hand, are used for generating replicas of the original pulses, but having a constant top amplitude (element 5) and, on the other hand, for eliminating mutual phase differences by means of phase comparison with local clock pulses (elements 7..14). The latter is preferably effected by the bipolar pulses being multiplied (element 7) by the clock pulses, and by using the resulting DC signal to control a controllable delay element (8).

Abstract: An apparatus for aligning monomode optical fibers utilizes a first optical coupler for injecting light into a straight section of a first fiber through its buffer, a first pin for bending the first fiber downstream of the first optical coupler to convert cladding modes into core modes, a second pin for converting core modes into cladding modes in a second optical fiber, a second optical coupler for withdrawing light from the second optical fiber through its buffer, and feedback control to optimize the amount of light transferred from the first fiber core to the second fiber core.