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[TowerTalk] TV tower/TA-33Jr/Ham-M combo OK?

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Subject: [TowerTalk] TV tower/TA-33Jr/Ham-M combo OK?
From: va3pu@rac.ca (Ed Pugh (VA3PU))
Date: Sun, 7 Oct 2001 20:01:06 -0400
Hi.

Just back in May, I got myself "re-activated" into Ham Radio after
a 22-year hiatus!  I am slowly trying to get back on HF.

Here at my home QTH, I have a small 40' TV tower (four 10-foot
sections).  This tower is located against the house, and is braced
from under the eves of the house, about 2.5' above the bottom of
the second section.  The rest of the second section (about 7.5')
and the top two 10' sections are "free standing" above the brace.

Currently, I have a dual co-linear phased 2M vertical (two 5/8
wave sections), above a small 4-element ground plane, on top of
the tower.

Just last week, I purchased a used TA-33Jr (the old version with
the single-piece 12' boom) and a Ham-M rotator (again, the "old"
version, with the brown, single-levered control box).

The TV tower does not have a "base plate" but just a simple mast
mounting inside the top of the tower.

I would like to mount the Ham-M on the mast, and mount both the
TA-33Jr and the 2M vertical on top (I cannot think of anywhere else
to put the vertical).

Should I mount the Ham-M on the mounting mast inside the tower and
put the rotating mast above it through the tower top, or should I
mount the Ham-M above the top of the tower?  I would think that it
would be easier on the Ham-M bearings to put the rotator inside the
tower, to allow the antenna mast to go through the tower-top, in
order to let the tower take the brunt of the wind-load instead of
the Ham-M bearings.  But then, would the mast bind in the cylindrical
fitting at the top of the tower?

Should I add guys at the top of the tower, or should the tower be
able to take the loading of the TA-33Jr and the 2M vertical?  Do I
need to add on the "torsion bar" recommended in the Ham-M rotator
manual?  (The Ham-M does NOT currently have any brake delay circuit,
but I would like to put in a "home-brewed" one.  I am also going to
ask about this in my next E-mail.)

Any other recommendations about the tower/antenna combination?

TNX ES VY 73,

Ed Pugh (VA3PU)
Ottawa, Ontario
va3pu@rac.ca
Ed Pugh   | A common mistake that people make when trying
VA3PU     | to design something completely foolproof is to
Ottawa ON | underestimate the ingenuity of complete fools.
CANADA    | - Douglas Noel Adams (1952 - May 11, 2001 :-( )

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