For top loading, only the ones which are FARTHEST away from the base
will count in the effective height. The 85 footer will do it.
Removing the insulating PVC from under the end 20 meter director, the
20 meter reflector, but NOT the driven element, will extend the
effective height and prevent various arcing problems using the tower
as a low band vertical.
W8JI has had a 160 dipole at 300+ feet, and his vertical still ate it
for lunch. **BUT** he also has a commercial grade ground system under
his vertical.
GOOD RADIALS are what will make it play.
73
----- Original Message -----
From: "George T. Daughters" <gdaught6@leland.stanford.edu>
To: <towertalk@contesting.com>
Sent: Wednesday, February 06, 2002 6:20 PM
Subject: Re: [TowerTalk] Shunt Feed Capacitor for Tower
On 6 Feb 02, at 16:28, James Hall wrote:
> I would like to shunt feed my 72' crank-up. The Carolina Windom 160
> in a inverted-V configuration just ain't doin' it ! I cannot even
> hear the S9LA station and the guys with the 4-squares are eating my
> lunch. There is no way to get that Carolina Windom horizontal
without
> about 700' of rope. I figure the most direct approach is to use the
> tower. It has good capacitive loading up top with F12 beams at 75'
> and 85' ( plus a plastic owl, but I won't go there !)
Remember that the F12 antennas have elements which are insulated from
the boom. I wouldn't be surprised if that made for a less-effective
top-loading effect.
73,
George Daughters, K6GT
______________________________________________________________________
__
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________________________________________________________________________
Where do you get ICE bandpass filters & beverage matching boxes? The
same place that pays for the hosting of this list: The eHam Store.
Order online at http://store.eham.net.
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FAQ on WWW: http://www.contesting.com/FAQ/towertalk
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