On 3/16/2021 7:14 AM, Mike Smith VE9AA wrote:
Most of the time through an A/B switch the verticals were close enough that
I would really be guessing which one was loudest/best and other times the
one with all the 60 on-ground radials was definitely best by a small margin.
The fly in the ointment with listening tests is AGC. A FAR better test
is A/B RBN testing, alternating between the two antennas for a half
dozen "TEST VE9AA" on one, QSY, then the other, pause 10 minutes, QSY,
repeat at least a dozen times, and average the results.
I did this recently to confirm a problem with one of my 160M antennas
that was suggested by responses (or lack thereof) to my CQs during a
contest. I plugged the reports into a spreadsheet, with the calls of the
reporting stations, averaged them for each reporting station, and sorted
them by azimuth to take directivity into account (the antennas I tested
have interactions that cause them to be directional).
The antenna that was underperforming HEARD a lot better than the one
that produced the loudest signal on the other end.
73, Jim K9YC
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