More for my own ongoing experimental notes than anything else, results for a brief test as the 14MHz band closed.
Conditions:
MW1CFN = vertical delta loop, 300Ohm twin feed/6:1 voltage balun/coax to RSP1a running SDRUno, WSJT-X, Parys Mountain.
MW6PYS = 1/4 wave vertical, two elevated radials, RG-8X fed (10m), to TS480SAT, Raspberry Pi running WSJT-X, open field in central Anglesey marshland.
As the band was almost closed as I started the comparison, only a very cursory comparison was possible, equating to +2dB in favour of the elevated quarter wave vertical (MW6PYS). Range was +6 dB to 0 dB in favour of the 1/4 wave vert.
One has to take into account the delta loop has about 3dB inherent advantage over the 1/4 wave vertical, as a delta is effectively a pair of close-spaced, in-phase verticals. So a delta loop placed on the marsh might yield up to +5dB over the delta at the home QTH, even though that delta is on highly mineralised ground.
The advantage is more likely to be a result of differences in electrical noise between the sites (there is effectively none at the marsh site).
Moderate RFI from the Raspberry Pi was drastically reduced by two methods: switching off the USB power connection to the Waveshare 7" LED screen once WSPR was running, and two windings of the cable to the ZLP data interface through a TDK ZCAT3035-1330 ferrite (originally supplied with my TS-480 for the cable between transceiver body and faceplate.
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