This is just a note intended to share some unexpected results.
I have a K9AY pair of loops at right angles and also a pair of DxEngineering
102" active verticals. Both are used only for RX. The two short verticals
are approximately 125 feet apart with their axis at 27 degrees East of
North. The K9AY loops are NE-SW and NW-SE. The two RX antennas are
approximately 150 feet apart --- maybe slightly more. An NCC-1 phasing unit
[DxEngineering] is used to phase the two verticals.
Last year I used the same setup and felt that the K9AY performed better ---
in particular because I could switch select the loops and their directions
and could often bring the desired signal up out of the noise. The two
verticals did have some noticeable signal improvement as the phasing
controls were changed, but the signals did not really seem to rise
significantly above the noise.
This year the phased verticals seem to be my RX antenna of choice. There is
either something that has been altered in the two antenna systems by the
snow-rain-ice-snow combinations during the December-January period or I have
found a better way to adjust the phasing controls of the NCC-1. In any
event, the phased verticals now provide the best signal to noise on the
desired signals. The phasing adjustments I am using are somewhat
non-intuitive and I found them only by accident.
At this point I am contemplating NOT re-installing the K9AY loops next
Autumn and instead looking at improving the phased vertical system --
probably by increasing the height of the verticals and perhaps top loading
them.
I would like to remind readers that this is only two Season's observations
and I have not figured out a way to make 'hard number' measurements to
quantify the differences I believe that I am hearing. The K9AY has not
'lost' its operational characteristics, but the phased verticals do seem to
provide better listening results than they did last Winter. I would also
point out that the area 'foot print' of the K9AY is a circle about 25 feet
in diameter and the phased verticals [as I have them installed] require a
straight length of about 125 feet. In my case there is nothing but air and
perhaps a few weeds between the two verticals.
Tod, K0TO
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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