Development of Prototype Double Sideband Doppler VOR Transmitter and Carrier Modulator

摘要

The equipments are for use in a Doppler VOR ground station. The double-sideband transmitter provides two 50 watt outputs, each phase locked to a carrier transmitter at 9960 cps above or below the carrier frequency. Two separate output stages are automatically frequency controlled by a phase control unit to obtain the two sidebands. The carrier modulator replaces the present conventional VOR modulator and extends the modulation capability down to 30 cps. The modulator is driven by an alternator on the Doppler VOR distributor and controls the phase of the 30 cps modulation signal automatically. The transmitter and modulator were evaluated for performance and the final design passed type tests in accordance with specifications FAA-R-777e, FAA-R-1402 and FAA-R-1403. (Author)