After Sunday's FreeDV net on 40m, my neighbour (1km away), Richard VK3LRJ, commented that he couldn't hear all the stations I was hearing. He's on a similar 5 acre block to me. I have wire dipoles in the trees and he uses an end fed wire cut for 80m but with in-line capacitance to resonate on 40m. Richard is off grid and has significant noise from his solar power system which I'm sure is a major factor.
To test our relative reception I suggested we both run WSPR in receive only on 40m so we can compare receive signal to noise.
I did some spot checks, looking at individual transmissions received by both of us.
VK7JJ at -8 vs +13 = 21dB.
VK2NSB -26 vs +19 = 45dB. Wow.
My reception was significantly better than his. For a more long term analysis I turn to the excellent WSPR data analysis site https://wspr.rocks/ and in particular the "head2head" page. For 12 hours of operation here's the spot count for each of us.
I'm not sure of the best way to compare reception but there are several charts comparing signal to noise. This is maximum SNRs.
Ideally I'd like to be able to have software which finds the same transmission as received by both stations and subtract the SNRs (as I did manually above).
Richard's end fed no doubt has complex nulls compared to the simpler pattern of my mono-band dipole but the charts show that overall his reception is significantly worse.
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