On behalf of all the club members I would like to thank our Chairman Matthew Twyman GW6KOA for his talk and demonstration of the 472khz band and especially his homebrew ‘active antenna’ based on a design by PA0RDT (Google – PA0RDT mini whip). I think his talk has prompted a few members to get their soldering irons out and to construct this very simple and cheap RX antenna….possibly a good construction project for the Intermediate licence also? Thanks Matthew.
The photo above is of 472 KHz, the area around the red marker is 472.5 KHz cw section. Yes, the antennae really is full size! The circuit uses a 2N3819 and a BC107. As you can see, strong signals were seen using a Finningley SDR. 73 de Matthew GW6KOA
Article on PA0RDT (PDF download 1.4Mb)
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