It's That WSPRing Time of Year Again!

With settled late autumn conditions over Wales recently, I've been tempted out with the elevated 1/4 wave vertical for 14MHz to the lakeside for a spot of WSPRing once more.

The lake isn't big, but the antenna is located on what is effectively a floating projection of shore and so has a very good ground. The image below shows the general situation, but during lower water in summer.

14MHz WSPR in 2022.

 

This time, I've been lucky to find someone to compare with who is happy to share details about his antenna set-up; this is not remotely as easy as you might expect for a communications-based hobby, more's the pity.

G4HSB runs a very nice, 2-element quad for 14MHz WSPR. For this purpose, he has it set at 300 degrees beam heading and the centre of the antenna is about 60 feet up. The expected 'inherent' gain for an antenna like this is between 11 and 12dB, meaning that terrain gain enhancements are not taken into account. That can be done, but it's a protracted process that needs accurate terrain modelling. It is more relevant to the horizontally-polarised quad beam and much less so for my vertical. Both stations are putting out 0.2W into their respective antennas.

 

The very nice 2-ele quad beam of G4HSB.

In contrast, the watery ground at my location can be expected to add several dB to the antenna's inherent gain; past measurements have seen 10dB being a typical figure above an identical antenna located on ordinary soil ground, although this benefit may be higher at times such as long path.

So, normalising the antennas to 0dB difference in gain between them, this is how KL7L in Alaska, a bearing of 343 degrees (~7000km), heard both antennas (click for larger version):

KL7L WSPR reception of MW1CFN and G4HSB with normalised gain, 12-13 Nov, 2024.

Of course, being 60 feet up in the air and with the benefit of some terrain gain, the quad beam remains in contact, albeit weakly, with KL7L in those periods when propagation is reduced. The loosely sinusoidal and slightly strengthening signal from G4HSB through the day and into the evening is interesting. It may be a product of changing optimal propagation angles relative to the quad's elevation pattern and/or ionospheric conditions, but that's a whole other area that I won't get into here!

Somewhat surprising is that the lakeside vertical - a fishing pole plonked in the ground, with three wires attached - is 1dB above or, in practice, essentially the same in mean signal as the vast quad beam up at 60 feet. Now, that's not much to celebrate if consistency of making contact through the day is the aim. But it's still a good result for such a simple, hand-portable antenna when compared to the sheer complexity and fixed nature of a HF beam.

As always, the message is clear: remain fleet of foot with your antennas and make use of watery environments to match or, quite often, beat HF beams! Portability, of course, also avoids that sinking feeling when someone installs RFI-producing equipment near your home; you simply grab your vertical and go somewhere quiet. 

24 hours WSPR coverage, 14MHz, vertical at the lakeside (0.2W) 12-13/11/2024