Abstract: A multifunction modular electronic apparatus for performing information technology and telecommunications functions comprises a first module (101) for performing a plurality of first functions; a second module (102) having substantially the same physical dimensions as the first module for performing second functions; and a hinging mechanism (103, 104, 105) for enabling the two modules to be mechanically coupled, to rotate relative to each other over a full range of 360 degrees while remaining stably mechanically coupled in any intermediate position over the range, and to be fully separated from each other.

Abstract: An electret microphone (10) comprises an electret diaphragm (11) having a thin metallic layer (13) deposited on one of its major surfaces. A ring-shaped metal washer (20) bonded to the metallic layer (13) of the diaphragm (11) by means of a lightly metal-filled adhesive (21).

Abstract: An electromechanical resonator, in the form of a single planar body, comprises a flexurally vibrating resonating element coupled at its midplane to a pair of torsionally vibrating couplers. Unwanted flexural modes in the resonator are substantially reduced by selecting a length-to-width ratio of the resonating element ranging between 3 and 4. A bandpass filter comprising a plurality of such electromechanical resonators may operate essentially free of spurious responses over a band of at least 200 kHz.

Abstract: An apparatus for stabilizing microwave oscillator circuits is disclosed. The apparatus comprises a dielectric resonator positioned in the vicinity of a microwave semiconductive device for completing a feedback path between two electrode circuits of the device. A dielectric spacer is positioned between the resonator and the electrodes for supporting the resonator and controlling the magnitude of coupling between the two electrode circuits. A folded mechanical structure is described wherein the oscillating device and the resonator are located at the fold for improving the frequency stability of the oscillator. The microwave semiconductive device may be a bipolar transistor or a field effect transistor.