This means little to my software incapable brain, but may be of interest to some readers: a Raspberry Pi mini-computer used as a basic 10mW WSPR TX up to 250MHz with a suitable low pass filter on the output. I know my old colleague Bob G3WKW has done something similar. I am impressed.
See https://github.com/threeme3/WsprryPi
Well I can confirm that the software does indeed generate WSPR signals. The C code has an oscillator offset compensation which had the authors setting left in, wrong side to mine so I took a while to find the signal. DT was -1.6 or so which was strange as the decode is on the same machine with same clock. On 28 MHz the decodes were intermittent due to some banana shaped traces. This was on my brand new cased pi so I couldn't get to the GPIO pins, but no problem when it is beneath the antenna. There is talk of having filters that can be switched by the GPIO. Further info on the Yahoo Group which I think can be read by non-members. http://groups.yahoo.com/group/Raspberry_Pi_4-Ham_RADIO/message/988
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