Topband: Shunt loading a Tower

[Adrian Rees (M1LCR)]

Hi
I have just got planning permission for a 75 Foot tower. I plan on putting a
Force 12 C31 XR (10-15-20) as well as a lightweight 50MHz and 144MHz yagis,
and a rotable 7MHz Dipole up.

I plan on running top band by using a Gamma match to feed the tower against
a good carpet of buried radials and a chicken wire mat.

My question is, does anyone here have experience of shunt feeding a tower
for top band, and, does anyone have a formula for calculating the match ?
What are you experiences, how good is the solution ?

(The formula is important as it will determine the type of tower I order,in
terms of seftion length as  I don't want to order a tower that although
telescopic, has the gamma match feed pint half way up a telescoping
section).

Thanks

Adrian Rees
M1LCR