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Subject:
From:
Colin McDonald <[log in to unmask]>
Reply To:
Blind-Hams For blind ham radio operators <[log in to unmask]>
Date:
Mon, 26 Dec 2005 09:34:32 -0700
Content-Type:
text/plain
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text/plain (32 lines)
Hi all:
I have an idea to build a loaded 20M vertical using 14 gage wire and a
length of PVC pipe.
First i would like to ask if anyone on the list has built something similar
to this and what are some of the design features.

Basically my idea is to take a half wave of wire, approximately 32 feet and
wrap it evenly spaced from one end of an 8 foot peace of PVC pipe to the
other.
The diameter of the pipe would be approximately inch and a quarter or inch
and a half.
I stated 32 feet, but i would calculate to get as close to a half wave of
wire as possible on 14.175MHZ and then cut about 6 inches off that.
At the upper end of the pipe i would mount a telescoping whip such as you
would see on rabit ears, and use this whip to tune the swr to a flat 50OHM
load.
I am not sure what to do about a counter poise or ground radials, but i
suspect this antenna would be fairly low to the ground and any radials would
be either on the ground, or very close to it...i suspect 4 to 6 15 foot
radials should suffice

any thoughts or suggestions on the design that could make this project less
of a waste of time, energy and materials?
A local ham has made one and claims it works wel, but i am somewhat
sceptical how well it works give that it is a coil and is fed rather low to
the ground.
I wonder if the feed line was fed through the center of the pipe and then
the main coil was tapped in the middle, half way up the pipe, if this would
be better or if it would exhibit poor characteristics.
 73
Colin, V A6BKX

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