PASSIVE_LONGWAVE

Published:2009/7/16 3:22:00 Author:Jessie | From:SeekIC

Uses VFO of amateur-band transmitter to supply heterodyne for bringing in frequencies below 450-kHz broad-cast band on amateur receiver, such as Omega navigation station on 10.2-13.6 kHz, NAA Teletype on 17.8 kHz, and GBR time signals on 16 kHz. L1-C1-C2 100.kHz input wavetrap for loran C can be omitted at far-inland locations. C2 is two-gang broadcast variable capacitor with both sections in parallel. Mount L2 at right angle to L3. Converter should be well shielded. Operation involves tuning receiver to bottom of any amateur radio band, on frequency equal to difference between VFO and that to which receiver is tuned. If VFO is on 7 MHz and receiver is tuned to 7.085 MHz, combination will be set for 85-kHz station. In USA, unlicensed transmission on 160-190 kHz is permitted with 1-W input and 50-foot antenna including length of transmission line. -M. Muench, Longwave Simplified, CQ, March 1976, p 41-42.



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