80_METER_DIRECT_CONVERSION

Published:2009/6/25 23:28:00 Author:Jessie | From:SeekIC

Portabl e receiver with directional ferrod antenna and ver-tical sense antenna was developed for radio foxhunting at 1975 Bov Scout World Jamboree in Norway, in competitions for locating four low-power crystal-controlled transmitters hid-den along 4-km course. Varactor-tuned oscillator provides 20-kHz tuning range with R9, ade-quate for the frequency used-3.566, 3.585, 3.635, or 3680 MHz. T1 is subminiature auto-transformer with 8-ohm and 2000-ohm sec-tions, for 8-ohm headphones. For high-imped-ance headphones, connect headphone jack J1 to lug 9 of T1. ON/OFF switch is not needed, L1 is 22 turns No. 28 enamel wound over two 10×95 mm ferrite rodstaped together. 01-06 are NPN high-frequency small-signal transistors.-N. K. Holter, Radio Foxhunting in Europe, QST, Nov. 1976, p 43-46.



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