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Richard Clark · February 13th 09, 08:40 PM posted to rec.radio.amateur.antenna

On Fri, 13 Feb 2009 11:00:06 -0800 (PST),
wrote:

My questions are these...
The ground slopes upward in one direction that I need to run a radial.
The radial will have to have an upward sweep in order to maintain the
clearance needed to walk under it. Will this be an issue?

Hi Michael,

No more than any other design - which is to say it will fit into the
solution without any more effort or problems.

The mast will be attached to my house to help support it. I can
insulate it from the mounting bracket with no problem. What I'm
wondering is with the fact of the mast being right up against the
house and not in the clear, how much will the performance of the
antenna be affected?

I would be more concerned with mechanical issues (like the moment arm
of the antenna ripping out a wall). Of course, this concern is rather
limited. As for the effect on performance - yes it will affect it. Do
you have any alternatives? If you do, those alternatives would
probably not bring any significant change (improvement or otherwise)
unless your home has metal siding (or metal mesh stucco). Wood is,
afterall, an insulator; and a house is largely filled with air,
another insulator.

I have come up with this idea of a groundplane because I don't want to
deal with burying a whole bunch of radials in the ground. Think it
will work?

You are probably going to have to tune the antenna, or use a tuner.
Adding the "necessary" X feet to the top might do it, but simply plan
on building in a match or using a tuner and be done with it as a
problem. As for the radials, this is an issue of loss. If you can
put up with the loss, you don't need a "whole bunch." How much loss?
Probably less than the width of an S-Meter needle variation between
what you plan, and what you might do in a full scale elaboration.

73's
Richard Clark, KB7QHC