Just a few more observations with receive antennas. This past year, I
did a lecture at the DX club about low band receive antennas.
Basically, I gave points for various characteristics of the antennas as
I employ them at my QTH. I compared the DX engineering circle 8 vs SAL
vs Beverage vs K9AY. Among the factors considered were cost, ease of
construction, size, usefulness, ease of repair, signals. The factors
were based on my experience with them over the last years. The
discussion was not limited to 160m but this was factored in. I added
the numbers and made this part of the discussion. What I learned and
presented was as objective as I could be. All things considered, the
SAL-30 was the best performing system considering all factors. If I had
to pick one antenna for receive, that would be the one. The circle 8
was the most expensive, by far. To be honest, mine is not optimized for
160m but is set at a compromise radius for 80 and 160, the radiators are
about 20' tall and I exchanged all the preamps for HiZ ones instead of
the original DXE. On 160m the coaxial bidirectional (900ft long)
beverage provided the best signal strength into EU. I did not find much
difference between a K9AY and the SAL-20. They all helped receive
stations. For the most part, I have Delta Loop antennas for transmit.
They are very noisy. So anything is better than them for receive. I
will say this, the antennas all stayed up last winter but this year we
had 6 ft of snow in two days just prior to the CW WW contest. Both the
SAL-30 and the beverage were destroyed and needed to be
repaired/replaced. I had the chance to fix the beverage, but it was
broken in several places where trees came down on the wire. The circle
8 was not broken at all. The K9AY was not damaged either. We had winds
of 70 mph plus during the storm. Large trees 8" in diameter were taken
down. Pines were decapitated of all foliage. The circle 8 is pretty
tough as I constructed it but it is just not a great 160m receive
antenna. It is good but not as effective with S/N ratio to the NE as
the beverage. I think some of my observations are latitude specific for
Western New York and I acknowledge that my location is very very bad on
antennas. Some of my yagis only lasted months before they were
destroyed by wind storms. I eventually redesigned almost everything
including the 4 Square vertical radiators that were severely damaged
last winter. That is it. In my case, physical design of the receive
antenna begins to be of paramount importance when considering
installation.
--
David J Rodman MD
Assistant Clinical Professor
Department of Ophthalmology
SUNY/Buffalo
Office 716-857-8654
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