And annoyingly it didn’t work

Stellar provide setup advice to fine tune the board and an introduction into the use of the WSPR software.

And this is where it all went wrong! When hooked up to WSPR http://physics.princeton.edu/pulsar/K1JT/wspr.html  and Spectrum Lab http://www.qsl.net/dl4yhf/spectra1.html  (the tweaking software Stellar recommend) I was seeing the square root of nothing.

After checking the component placements and solder joints at least half a dozen times I was sure the board was built correctly. Stellar’s tech support team provided some advice and trouble shooting via email but unfortunately that got me nowhere. By then the big guns in the form of Graham (M0CYX) and Andy (G7UHN) http://alloutput.com/amateur-radio/loft-receivers/  we’re brought into play along with other members of FPARC (Fort Purbrook Amateur Radio Club) http://www.fparc.org.uk  who all provided great advice and guidance.

The problem was eventually found in the RX side of the circuit where J3, the antenna connector sits. The PCB is double sided and the antenna connection feeds a track which runs along the top side of the board. There was no copper between the upper and lower sides of the board at that connection, so unless electrons were going to learn how to jump, nothing was ever going to be received by the circuit. A quick repair job with a short length of wire from a resistor leg between J3 and C15 and we were up an running.

If you need to fault find this board start by plugging a set of headphones into the board or pipe the audio of your mic/line in through your soundcard so you can hear what’s going on. WSPR tones are unique and you’ll hear them over the background noise. No tones means somethings wrong and it’s time to check for voltages and continuity on the board.

Anyway, with 5m of single core wire as an antenna and another length for the counterpoise we were up and running

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