An interesting afternoon’s 50MHz WSPR; propagation near and far

I mentioned yesterday that I had got WSPR-X running and tried it out on 50MHz.

Despite it not being the most active of 50MHz days, it actually proved to be very interesting. Later on in the afternoon there was some Es around and I was pleased to spot and be spotted by CN8LI at a distance of just over 2000km. Not bad for 5W or so.

But actually, the most interesting signals were from Roger, G3XBM over in Cambridgeshire at a distance of around 140km. Roger runs 1W to a vertical, like mine. Pretty much every transmit period he made, I could see his signals, although often insufficient strength to decode. Another challenge was that owing to the amount of aircraft in the skies between us, the signals were often heavily doppler shifted, which is a problem for WSPR.

To our delight, Roger was able to decode my 5W signals several times and I was able to decode his 1W signals on several occasions. Our suspicion was that tropo came up a little and that there might have been some assistance from aircraft, perhaps flying on such a path that there was limited doppler shift.

I did also note that on the couple of times that we exchanged signals, Es had bubbled up a little. Clearly there is no suggestion that the propagation was via Es. However, I did wonder whether there was some benefit from some sort of scatter associated with the Es. At such low powers, I’m doubtful, but will look to see if it happens again.

Tim Kirby, G4VXE, is a regular contributor to and writes from Oxfordshire, England. Contact him at [email protected].

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