If a test field were set up such that the monitor antenna
and device-under-test were 10 wavelengths apart, and such that
there were 10 wavelengths free space around each antenna in all
directions (except below), then there is a hope that reasonable data can be
taken.
In that case, the monitor antenna could be raised, to take data
at different elevations....and, in fact, might want to be
somewhat closer to the DUT.
Although I don't know the details, I note that both Chuck at Tennadyne,
and the Mertels at Fluid Motion based their specs on test range data.
They both work as advertised. AND, in my opinion, either will outperform
a trapped tribander on 20, 15 and 10.
The exceptions to that? The flock of multiple-monobanders on a common boom
Bencher skyhawk, Opti, and Force 12. They tend to be 1-2 dB better at their
best frequencies than the SteppIR, and 3-5dB better than the tennadyne.
They also tend to have longer booms.
M2 fans will note that I left them out. The KT34A was the best small
antenna
I'd ever owned...until the SteppIR. The XA was better, but not on 15
meters.
I owned three of them, at various times. The M2 versions are reportedly
quite
good, although I haven't owned any.
Like most guys, I don't have an antenna range, so this is based partly on
personal
experience, and partly on second hand annecdotal evidence.
The reality is, a better informed customer group would result in more honest
antenna specifications. The better firms, today, have taken the lead in
educating
their customers. The others simply take advantage of customer ignorance.
N2EA
jimjarvis@ieee.org
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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