LF: 500kHz transverter testing this evening

[Roger Lapthorn <rogerlapthorn@gmail.com>]

Dear LF,

My 10W RF out MF transverter has now been built onto a small board "dead bug" style ready to put in a small plastic or diecast case.  It is for use with my FT817 receiving directly on MF (rig in split mode) and TXing on 3.7MHz transverting down to either 472 or 500kHz using a 3.2MHz crystal.  

The design uses a 2N3904 mixer as in the LF Today book followed by a low pass filter with a couple of 22mm diameter coils as per the GW3UEP design approach in the IRF510 PA. It all seems to works fine and needs no expensive or hard to find parts. I'll put the current schematic and photo in the files/photo section on the Group website. Feel free to copy and, I expect, improve on it.

This evening I propose to test this on WSPR and OPERA on 500kHz with an ERP of around 50mW (antenna improvements are next on the list).

As before I am very happy to give and receive reports. Assuming no snags, the rig should be on air until around 2200z tonight.

73s 
Roger G3XBM

-- 
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