Siemens Aktiengesellschaft

Hans Albsmeier

Wilhelm Volejnik

Friedrich L Kuenemund

Karl Traub

A carrier frequency communication transmission system has a premodulation band above the transmission position of the base primary group of 60-108 kHz and utilizes mechanical filters as channel filters and also a common group filter in order to filter out the primary group band. Bending resonators having longitudinal coupling are utilized as the mechanical filters. The frequency range of the premodulation band at its lower limit is determined by a frequency spacing of at least 4 kHz from the upper band limit of the primary group band and the upper limit of the frequency range is determined in that the interfering natural oscillations, inasmuch as they occur in the lower stop band of the channel filter, lie at least 12 kHz below the lower limit of the primary group band. Highly stabilized piezo ceramics is used as the electromechanical transducer material.

Growing community of inventors

Munich, Germany

Hans Albsmeier