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Dave Oldridge · February 17th 09, 06:15 AM posted to rec.radio.amateur.antenna

wrote in news:2477b02a-bc76-4a0d-a04d-
:

I have a Rohn 30 foot telescoping mast that I'd like to use as the
vertical element of a 40 meter ground plane. My idea is to add 3 feet
of pipe to the top of it to make it the required 33 ft. long.
I want to elevate the bottom of it about 8 feet of the ground and run
a couple of quarter wave wire radials out from it. This way they can
be walked under.
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?

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 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?
Tnx for any advice and suggestions and 73,

I modelled this the other night over a 15-degree slope

Basically, the pattern will have only about a 10db null. The pattern
will be good at low angles downslope and a bit raised upslope. The
antenna will even be half decent for NVIS at medium distance downslope.

In short, go for it!

--
Dave Oldridge+
ICQ 454777283
VA7CZ