Topband: Short Verticals

[David Cutter]

As I understand it, if you reduce the effect of ground loss by using raised 
radials you should get a more predictable and consistent result.  So, your 
main radiator, the vertical, sits between 2 sets of radials, one set at the 
top and one at the bottom.  My feeling is that this gets the most efficient 
result.  Most software doesn't like radials close to or in the ground, so I 
would do the modeling then make one to do real measurements.  From there you 
can plug in accurate figures for your phasing system.

I came across this, which you probably know all about: 
http://www.kkn.net/dayton2005/ON4UN-Dayton-2005.pdf

Will you be using wires, poles or towers?  Wish I had the space.

David
G3UNA


----- Original Message ----- 
From: "David Cole via Topband" <topband at contesting.com>
To: <topband at contesting.com>
Sent: Tuesday, June 13, 2017 10:08 PM
Subject: Topband: Short Verticals


> Hi all -
> Assuming a standard 1/4 wave vertical is 36 ohms - is there any formula 
> that will calculate the Z if the vertical is short and brought to 
> resonance by top loading wires - I understand the Z will be less - but how 
> much by ? I am trying to use the formula on ON4UN disc to calculate the 
> approx LC ratios for a Lahlum-Lewallen phasing system.
> Thanks Dave g3rcq
> _________________
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