Lockdown Exercise

How's your Covid-19 lockdown going by now?  Here in the Disunited Kingdom, Government guidance has become hoplessly confused with what is actually law, leaving most of the population, police and even the ministers themselves, lost as to what we are and aren't allowed to do!

Worse, the guidance and laws are now increasingly divergent between England and the other nations of the UK.  For the first time in centuries, there is now, in a very real effect, an enforceable border influencing people's movements between England and the other nations.  You can now go out in your car to find a nice place to exercise in England, but fined by the authorities if you happen to stray into Wales or Scotland to do the same. The population is slowly deciding there is so much confusion that they will make their own minds up as to what they can and can't do.

Sticking to the laws of Wales, I took my exercise last evening for an hour or so on the most northerly point of our little country.  Whilst I went for a walk, I left my new Raspberry Pi-RSP1a SDR receiving system listening to the world's WSPRs.  On an evening where a brisk northerly breeze was coming straight from the North Pole, one could certainly feel that Anglesey is not so far from the Arctic!

Backpack SDR WSPR reception, from Wales' most northerly point.

I've previously tested this area with a WSPRlite transmitter, and found it isn't as good a place as one might imagine.  That's partly because the ground underneath the antenna is very rocky and therefore prone to high losses, and partly because, being a north coast, it is looking towards an area of the planet where signals are not, in general, coming from.

The SDR receiving system still amazes me for the fact of its operation from a handheld USB battery, and tiny, now ageing Pi 3B+ palm-sized computer.  The only difficulty I had with the whole thing was getting the audio input levels - far too high, but still decoding, - set properly from Cubic SDR into WSJT-X.

The answer was obvious, but not on a 7" screen in strong sunlight, with everything crammed into a very small space!  The audio gain setting, which I had to reduce dramatically, is found on the extreme top right of the panel, as indicated here:

Cubic SDR panel.  Image: CubicSDR.com

Once that was done, I could leave it to its own devices and complete my walk!

The results were largely as expected.  For signals from the far west US, the north coast location was 5-6dB worse than the delta loop back home (only ~3 km away).  Allowing for the delta's inherent better gain over a 1/4 wave vertical, this is, roughly, the two antennas hearing equally well.  I would have expected better for western US signals, because their path brings them in from a NNW direction, where the sea could be expected to yield a better result.

The one exception to this rule, when allowance is made for the different antenna gains, was AA7FV, who has a large rhombic pointed very narrowly at Europe.  The signal here was equal in both antennas, meaning the 1/4 wave vertical at the coast was, in effect, hearing him ~3-5dB stronger than the delta.

Looking at Scandinavian signals, the situation was much the same, with the coastal vertical matching the delta loop at home (in other words, potentially hearing ~3-5dB better from the coast, allowing for the different inherent gains of each antenna).  One station, SM3DTQ was different, showing a 7dB enhancement at the coast (potentially, ~10-13dB better than the delta, allowing for gain differences).

It's a shame this location doesn't yield better enhancements, as it's a beautiful and peaceful place to work from for an hour or two, only five minutes away from home.  It seems I'll have to eventually spend more time driving to the west and east coasts for the best enhancements, which are certainly worth the effort! 

Meanwhile, you can spend a few minutes of your lockdown watching this video from the US, which is pretty much exactly what I have done: