Terminal and repeater equipment in new technology for demonstration of future trunk telecommunication on existing TEO1 mode circular waveguide sections project part: Demodulator, base band regenerator, PCM simulator, second down converter, and IF amplifier

For a research project concerning digital transmission via TEO1-mode circular waveguide, the following components of a repeater were developed: second down-converter, IF amplifier, demodulator, signal and clock regenerator, and encoder. Four samples of each of these units were developed. A complete error-rate measuring set was developed and fabricated. For the development of the demodulator and regenerator circuitry, simultaneously with the other components of the repeater, a test generator was made which delivers a sinewave of 1254 MHz, phase-keyed at a rate of 264 Mbits/s. The down converter is an unbalanced Schottky-Barrier-Diode mixer; the wideband transistor IF-amplifier consists of 7 stages. The automatic gain control is obtained by a regulated PIN-Diode attenuator. The technology is stripline technique on PTFE-substrate. The demodulators for signal and clock extraction (2-PSK on a 1254 MHz IF carrier) were realized using thin film hybrid technology; signal and clock regenerators were built on a printed-circuit board using miniaturized components. The subgroups of the error-rate measuring set contain mainly integrated ECL circuits.