Hello Topbanders,
My current 160 meter antenna, a 45? top loaded affair, has served me pretty
well, but I wish to replace it with something taller; preferably, for aesthetic
reasons, one not involving a tower. I think for my urban lot a reasonable
height limit is probably about 75?. One of the European verticals probably
isn?t a realistic option for me, so that has left me pondering a homemade
vertical antenna, which would be constructed of aluminum tubing from the common
amateur radio sources. I?d love to use irrigation pipe, but I don?t find any
distributors listed in the local yellow pages. So that may not be an option for
me. Also, I am not sure how I one goes about transporting the pipe to their
house?
A few years ago, a ham on the list sent me his design for a 70? vertical built
from 6? or 8? tubing sections. The base sections started with something like 2
¼? tubing and were progressively smaller in diameter to the top. It must have
been a challenge to erect the lengthy noodle, but he said he had built and
phased 2 of them together. I never asked him, but I suspect he used a gin pole
to orient them vertical.
Although I had the usual ME classes in college years ago, I only have a general
feeling for what constitutes practical diameters and lengths for the vertical
sections. I?ve thought about starting with three, 6? sections of 2 ½? tubing,
coupled together using smaller internal pieces of tubing and then following
that with progressively smaller diameter sections. Like my current vertical, I
plan to use a wire capacity hat to top load the antenna. Therefore, the upper
sections would have to support the wire weight.
If you have experience successfully building such an antenna I would appreciate
hearing how you did it - and of any pitfalls you encountered!
Thanks & ?73, Thomas ? AC7A
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