Topband: Shunt Fed Tower Info

[Cqtestk4xs at aol.com]

I have been workling on some ideas for 160 transmitting antennas and need 
some input.

I am in the process of finishing off putting Polyrod fiberglass cable and 
Phillystran on my 40 meter tower.  At 199.9 feet and 90 feet are KLM 4 el 40 
meter beams.  In the next month or so, I plan to install the six 6 6-element 10 
meter beams on the same tower.  When completed the tower will have the Polyrod 
and Phillystran to around 15 feet of the anchors, leaving a virtually 
'electrically clean' environment.  All cables will come off pretty close to the base of 
the tower except for the 1 5/8 hardline which require a decent size bend at 
the bottom.  I also have room for most of the radials to be 130 feet or so...if 
I annex my neightbor's unused land.

What I want to do is shunt feed the tower and have a system of 4 wires 
suspended at right angles to each other to provide switchable reflector/director 
like I have seen in several publications.  Getting the height and the distance 
for the relectors/directors will not be too much of a problem.  However, I am 
concerned about the height of the tower being used as a radiator.  A rough guess 
is that the top loading of the tower by the boom of the KLM 40 meter antenna 
would make the tower around 230 feet or so.  The boom is totally insulated 
from the elements so I think the elements would have a relatively small effect on 
the total effective height.

I have two questions.  First, is the 230 feet or so of effective height too 
tall and and would I be at a disadvantage to a tower which had an effective 
height of around 130 feet?  I know the lobe changes as the height passes1/4 
wavelength.  Second, is a system of some elevated and some buried radials fraught 
with problems.  I would like to elevate some of the radials to 10 or 15 feet.

Anyone who has been down this road or who has some ideas about this system?

Thanks for the help.

Bill K4XS