Today I completed the rev E version of my 10W transverter. In the end I reverted to a double balanced mixer and this immediately solved my issues with mixer stability that I had with the transistor mixer design. Air testing this evening, I am getting plenty of reports but a slight drive is noticable in the reports, probably as I am using a small plastic box and the PA heatsink warming is causing the 3.2MHz crystal to move about 1Hz during the WSPR TX cycle. It really needs a bit bigger metal box, but it will do.
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| The lastest transverter schematic (there may be value errors) |
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| WSPR reports 20.9.12 with the above transverter and 6m long antenna |
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| The desktop 472/500kHz station, ATU (don't laugh!) and antenna current meter |
Looks interesting, I might be tempted. If you were going to publish perhaps worth having a mod for those who might want to put 5 watts in from an FT897 or similar. Probably use 10x560 ohms for the input load.
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