[TowerTalk] Fwd: Verticals on a Hill

[Hans Hammarquist]

 Doing service in the Signal we were told to, if possible, find a slope that there facing the other station in the downhill direction. That seemed to work both for HF (2 - 12 MHz) and VHF (50 - 70 MHz). There must be some truth to it.
Also, if you think about it; If you shift/turn the radiation pattern with the sloping ground you do getter lower radiation pattern in the downhill direction and higher radiation pattern in the uphill direction. I assume we want the lower angle for better DX.

Just my nickel,
Hans - N2JFS 
 
 
-----Original Message-----
From: Bill via TowerTalk <towertalk at contesting.com>
To: towertalk <towertalk at contesting.com>
Sent: Sun, Jan 20, 2019 8:07 am
Subject: [TowerTalk] Verticals on a Hill

Several people have mentioned the effects of a hill on a vertical or vertical system.  
I also know of no program that allows terrain to be considered for a vertical.  Several people who I consider informed came to the same conclusion I did, it enhances the signal if it is a downhill slope and is detrimental if is an uphill slope.  For example, if one looks at a Yagi at one wavelength over flat ground and then at one over sloped terrain, you can see how the angle has dropped.  Likewise, if you look at the flat results and then the print out of the uphill slope, it is easy to see the low angle has been attenuated.
It's my belief and some antenna gurus, that the steeper the slope, the lower the angle if down slope, and the more attenuated if up slope..  At my QTH I have a huge downward slope to EU and NA and a huge up slope to the top of Mauna Kea (14000 feet) which is LP for EU and SP for VK/ZL.  On 80 I have a 4 sq and on 160 a bent vertical and a very good symmetrical ground system.  For the same conditions and distances I can tell you the signal is much better in the direction of the down slope  than the up slope.  Is it a scientific test?  No.  However, it does indicate that if one has a big slope (in my case a 1:6 slope uphill and downhill.) it does affect how a vertical performs.  Mine and several others educated guess?  Going downhill at my place probably lowers the angel at least several degrees.  No, I'm not sure if the angle is elevated in the up hill direction.  No doubt though it is attenuated.
Those who have heard  me on 80 and 160 in EU and NA will agree that the down slope helps the signal.
Bill KH7XS/K4XS
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