> Recently on 75 meters while calling the same station, I was reported
> as 2 s units better than another station. I was using my rain gutters
> for an antenna, the other station was using a rhombic. Since an s unit
> is typically 6 db, I have therefore determined that my rain gutters
> have 12db gain over a rhombic.
Years ago, after being involved in some double-blind medical device
testing, I did a test on 75 meters where I compared a G5RV and a
"something" (I think it was a "full-size dipole" or "loop").
Quite a few operators reported the G5RV weaker during A-B tests,
sometimes the difference was significant even if I repeated the test
several times to "factor out" QSB. On two or three occasions
operators would say the G5RV had "less audio" or "poorer audio"
even though it was just as strong!!!!
(I remember one guy saying "you won't believe this but your audio
is actually better on the xxxx")
The most amazing part of this test is I wasn't changing anything at
all! I was tapping the PPT switch and making a click, and then
saying the fictitious name of the new antenna.
After that, whenever I changed antennas in a real test, I never told
anyone what they actually were. If they found out, I occasionally
would swap antenna positions between A and B.
I did that in several hundred A-B comparisons of a dipole at 300
feet and a 200 foot vertical on 160 meters, where the VK's and ZL's
would learn what antenna A and B were. Once they never knew
which was which, the reports were more "honest".
The dipole at 300 feet was statistically improved (but not enough to
be a winner) if people knew or suspected when I was using it.
When they didn't know which was which, the vertical was an even
bigger winner!!!
Weird, but absolutely true!
73, Tom W8JI
w8ji@contesting.com
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