Towertalk
[Top] [All Lists]

Re: [TowerTalk] Impact of high water table levels on antennas

To: "Rudy Bakalov" <r_bakalov@yahoo.com>, "TT TowerTalk" <TowerTalk@contesting.com>
Subject: Re: [TowerTalk] Impact of high water table levels on antennas
From: GARY HUBER <glhuber@msn.com>
Date: Sun, 3 Nov 2013 13:42:53 -0600
List-post: <towertalk@contesting.com">mailto:towertalk@contesting.com>
Rudy,

I have a similar situation. My QTH is on a glacial moraine about a tenth of a mile from the crest. There is water bearing clay less than thirty inches down and the soil is the black muck left by the glacial ponding. To top it off, I've mounted my HV-2 w/160m mod and umbrella capacitance hat over two dozen 66 foot radials all over the septic leach field. A friend who has operated from ZF2 and C6 numerous times says I am very strong using the HV-2 on 40..... I've worked a lot of DX with the HV-2 over the septic field over the past 27 years including ZL9CI, KH1, KH6, etc.

I believe the high water table helps me and will help you.... but the advantage works also for the 4SQ or any antenna. Probably about 3 dB from the Fresnel reflection.


-----Original Message----- From: Rudy Bakalov
Sent: Sunday, November 03, 2013 1:02 PM
To: towertalk@contesting.com
Subject: [TowerTalk] Impact of high water table levels on antennas

Ever since I have put up two inv-Vs, one for 80m and one for 160m, with their apexes at roughly 90', I have been puzzled by their exceptional performance. Ditto for my vertical on 40m. I have done tons of comparisons using skimmer data and my signal seems to be pretty darn close to the big stations I am using as my benchmark. The performance is so good that I have been wondering if I should bother with building 4SQs. I have read tons of books on antennas and the performance of these two antennas simply does not match what the books describe.

I shared my thoughts with a friend of mine (a WRTC2014 participant) and he shared a similar experience with his station. He recently relocated to a new place, about 30 miles from his old place, and his antennas at the new place perform significantly better than the old location. Same antennas, tower, feed line, and FLAT terrain. His only explanation is that the new place had a very high water table that somehow impacted antenna performance.

This is when I realized that I also have a very high water table. Even in the driest months of summer, the area around my tower is damp and the grass is very green, growing like crazy. This was the obvious common element between his and my situations.

I have not seen anything on high water tables in my antenna books. The soil itself is mostly sandy. The impact I believe I am seeing is mostly on the lower bands, but I am not sure if this is also the case on the upper bands as at 105' my antennas are a bit too high.

Is there any rationale in our thinking? Can high water table explain better than expected performance from low band antennas? If so, what is the theory behind it and how do I take advantage of it? If not, any other suggestions for why the antennas work so well?


Rudy N2WQ
_______________________________________________



_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________



_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk

<Prev in Thread] Current Thread [Next in Thread>