As one of the report authors, I thought I should jump in here.
The antennas were working models, borrowed from their owners for the
tests, and assembled following the manufacturer directions to the
letter. The antennas were returned to the owners and reinstalled,
continuing to be used on the air with no reports of significant
failures. After a first test indicated problems with a PRO-57 we
offered to test a new antenna from Mosley in the second round but they
declined for whatever reason.
The main issue with the Mosley PRO antennas we tested was on 10 meters
where gain and pattern were definitely below spec. It is quite possible
that the manual's instruction not to use a balun at the feed point
allowed significant feed line interaction to the point of upsetting the
radiation pattern. All other antennas did use a ferrite bead balun made
by Force 12. We did not test the Mosleys with and without a balun -
there wasn't enough time and energy.
On the other bands tested (20 and 15 meters) they performed more or less
in line with what you would expect from their boom length as did other
tribanders such as the KT34XA, C31XR, TH11DX, Skyhawk, etc.
It would not be fair to characterize Mosleys as chronic underperformers
across the board - numerous stations report good results from them. For
example, K4RO has a pair of PRO-57 beams and does quite well (his QTH
has some rather dramatic topography to work with). I don't see a lot
of Top Ten stations using them and you can read into that whatever you
want. Although the electrical designs are pretty long in the tooth, the
antennas are sturdy and robust - they stay up and withstand the elements
pretty well. There are other considerations such as operating bandwidth
or wind speed rating that might be more important than forward gain to
some customers. Antenna selection is a complex situation with a lot of
moving parts.
All of the data and the methodology is published in the report. I've
wished another group would tackle reproducing the results but this is,
after all, a leisure activity :-)
73, Ward N0AX
On 12/3/2013 8:59 PM, towertalk-request@contesting.com wrote:
I have no idea whether your Mosely performs well for it's boom length.or
>not.
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