The following private message to Pete-N4ZR is sent to the reflector
at Pete's suggestion.
73 de Dale, K5MM
>Date: Thu, 30 Apr 1998 03:29:30
>To: Pete Smith <email@example.com>
>From: Dale Jones K5MM <firstname.lastname@example.org>
>Subject: more - Precip static
> Pete: Your comments below are most interesting, and in particular
> when viewed together with the comments made by LB-W4RNL. In the
> past, beginning at N5AU's big station in Dallas, and my own station
> in Oregon a few years ago, I had multiple antennas for all bands,
> and they were all at different heights.
> For example, had a modified 205BA at 110 feet by itself, a 204BA
> side mounted at 70 feet on a second tower (with other antennas
> above it), and then thirdly a TH6DXX on a crank-up tower with only
> that antenna on that tower, which was usually cranked up to about
> 60 feet.
> Oregon gets lots of rain in the autumn, winter and spring, and
> my QTH was up on a hill where it snowed some in the winter too.
> During contests in the autumn, winter and early spring, the
> propensity to get rain during contests was very high. On 20
> meters for example, when rain static and snow static came along,
> the very highest antenna (205BA) was worthless. It would generate
> 20db to 49db over S-9 static on the receiver. The lower two
> antennas would not send virtually ANY static down to the receiver.
> Clearly, if I had only the high antenna, I would have been QRT
> during extended periods on time during the contests. Fortunately
> the antennas ALWAYS enabled me to stay on the air.
> I do not have any data showing these results --- too interested in
> contesting at the time --- but having those additional antennas
> made the difference between being off the air, and continuing to
> work sttions. I recall thinking at the time....the high antennas
> must catch the static as it falls out of the sky first and then
> dissipate it before it gets down to the lower antennas. That was
> just my ignorant supposition at the time. That might be a correct
> supposition, but if so it's only luck, and not a clear understanding
> of what's going on in the atmosphere.
> Same thing occurred at N5AU's station years ago. On 20 meters
> at Gordon's QTH, during 'static' times, the 4 element Quad was
> far superior to the high Yagi's. A huge difference existed between
> those antennas. High yagis were at 120 to 175 feet or so, and the
> quad (closed loop antenna) was at about 60-70 feet, So, two
> advantages to the quad--closed loop antenna and low to ground
> when compared to the yagis.
> Dale K5MM
> Pete: you wrote:
>>Amen ... in earlier discussions, many people have also observed anecdotally
>>that high antennas are more affected than low ones, and that some
>>rainstorms are much noisier than others. Anyone run across a
>>systematic study in the literature?
>>Time and again, I've found that one rainstorm will be relatively
>>quiet, while another (with similar rainfall rate and presence or
>>absence of lightning) will generate S9 +20 dB noise.
>>73, Pete Smith N4ZR
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