Saturday, 14 September 2019

Tantalising.

Warm weather returned to North Wales for this weekend, allowing a good chance to take a vertical and WSPRlite down to the beach.

Friday evening, with everybody taking to weekend radio operating, isn't the best time for WSPR.  I had also forgotten to change the settings on the WSPRlite from 5mW to something a little higher.

Still, I set up in front of the advancing spring tide, and set the little box off at 14MHz.  The beach, though exceptionally beautiful, is not ideal because of mountains to the east, and some low ground to the west.  The clear path is to the south.

Nothing quite like beach operating.

Well, I didn't manage to get terribly far!  The tide was also so big, and the beach so shallow sloping, that I had to keep moving the antenna every ten minutes or so.

Still, I did manage to get a -08dB signal into EA8BFK, which is on a direct, sea-only path from the beach.

So what?  You might say.

Well, if we take the three other stations being heard by EA8BFK at or very nearly the same time, things become exciting:

My 0.005W gave -08dB.  G0CCL, at 5W (30dB more power than mine), gave +4.  Allowing for the power difference, my signal was 26dB stronger than G0CCL.

A station in Jersey, GJ7RWT in a nice middle-of-the-sea location, achieved -17dB fro 0.2W.  Allowing for the power difference, my signal was 25dB stronger - matching the situation found with G0CCL.

Meanwhile, 2E0NPL managed -14dB from 0.5W.  That equates to my signal being 26dB stronger - once again, very beautifully matching the previous two results.


So, this admittedly very limited result gives us a tantalising glimpse of what is possible from the water's edge at the beach: a mean signal enhancement of 26dB over non-coastal sites.  This compares with an advantage of about 15dB I saw on listening tests with my mobile whip from the car, with a greater distance from the water.

In other words, dial in 1W on your portable transceiver, and you get the equivalent of 398W out!

I'll now build on this result and set-up again on a beach with a clearer aspect.  I'll also raise the radials a little.  Even though those mountains and other areas only reach about 2 or 3 degrees in apparent height, those low angles they obstruct are crucial.

Now enjoy a couple minutes' relaxation, exploring SW Anglesey:

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