This evening I've been noting my WSPR S/N reports from stations across the country and nearer Europe using my 9m long Marconi antenna (an average arrangement for a small garden plot like mine - but not the best) and comparing these with the reports last night when I was using just the 15m baseline earth-electrode "antenna". I crudely plotted the "improvement factor" in dB on a polar plot. Each dot represents a station reporting my signal with the dB improvement over the earth-electrode antenna plotted on a 0-20dB scale out from the centre. This is not good science, it is G3XBM science I'm afraid, but it give a fair idea of the difference and how direction affects this (see attached rough polar plot).

Although in some directions the difference is very little, in other directions the reports are up to 14dB better on the (omni-directional) Marconi.

My conclusion is that the earth electrode antenna is behaving somewhat like a loop with some directionality along the line of the earth-electrode baseline and a null off the sides. With stations receiving me off the sides there is most improvement with the Marconi, and less difference with stations end-on who were getting a reasonable signal with the earth-electrode antenna.

CONCLUSION: the simple, stealth, earth-electrode antenna is a VERY useful antenna on 472kHz as long as one is prepared to accept a 2-14dB loss compared with a "small garden" Marconi. In all honesty, I am getting better reports on the Marconi but few new stations are copying me: most could copy me on the earth electrode antenna.

73s

Roger G3XBM

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