DIRECTION-FINDING DEVICE HAVING A TWO-CHANNEL WATSON-WATT RECEIVER

摘要

1525778 Radio direction-finders LICENTIA PATENT VERWALTUNGS GmbH 7 June 1976 [7 June 1975] 23463/76 Heading H4D A direction finder with a conventional twochannel Watson-Watt receiver 12 and indicator tube 14 includes a switching device 11 for selectively connecting a small-base Adcock 1 to 4 and a large-base Adcock 5 to 8 to the receiver to obtain coarse direction-finding α 0 from the smallbase antenna and then a correction value #α from the large-base antenna. The two antenna arrangements are concentric, Fig. 1. Switching device 11 first supplies the direction-finding voltages of Adcock 1 to 4 to the receiver 12 so that the coarse direction-finding α 0 , is shown on indicator tube 14 via a fast time constant circuit 13. Then, for a short period during which the writing beam of tube 14 is disconnected via a scanning line 15, the directionfinding voltages from Adcock 5 to 8 are supplied to receiver 12, digitalized via A/D converter 16, and passed to an arithmetic unit 17. The unit 17 also receives frequency information from the receiver via line 20. The correction value #α is passed via output 18 of unit 17 to a follow up device 18SP1/SP by which the azimuth scale on indicator tube 14 is rotated so that the corrected bearing angle α = α 0 + #α is indicated. At the same time the corrected bearing angle α is outputted at output 19 of unit 17.