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[TowerTalk] roof tripod

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Subject: [TowerTalk] roof tripod
From: aa0cy@nwrain.com (Bob Wanderer)
Date: Wed, 3 Jun 1998 18:09:16 -0700
Looks like I'll probably wind up roof-mounting a vertical antenna
to get my station back on the air. Because the chimney is too close
to the ac power and drops, the best alternative is a tripod or quadpod.
Some questions: 
        What would be the best tripod height to handle a ~25-29 foot vertical
in the Seattle, Wash. area considering, too, ease of installation (of both the
tripod and the antenna onto the tripod). Without expertiese or experience, 
I'm thinking a 3-footer would do the job nicely. The antenna will be either 
a GAP Titan, Cushcraft AP8A, Hy-Gain DX-88, or Butternut HV9 (?). I 
own the first, but it was a bear to erect and "de-erect" on the ground; I can 
imagine what it  will be like on the roof. I have a potential source for 
the second. This model and the third choice concern me, however, 
relative to their being trapped antennas, although I have used these 
types for years and have been satisfied with their performance 
(perhaps because I had no other antenna up to do
comparisons). The Butternut, like the GAP,  looks like it may be difficult to 
install
and I have heard that they are prone to being easily damaged by winds. I would 
like
to avoid guying if I can; I know the [ground-mounted] GAP survived the very 
high winds northern Nevada is (in)famous for without being guyed (although 
a Challenger did not).
        Is there a source for a well-built tripod or quadpod in the local area? 
The IIX
products look well-built, but I don't believe he has one of the height I'm 
seeking; I
think he starts at 6'. I'm also beginning to suffer from the dreaded tropical 
disease
lackamoola so I want to keep costs down wherever possible (without sacrificing 
the
needed level of quality).
        I have been told (although I no longer remember the source or whether 
that person
was just trying to pull my leg) that stuffing a mast down the bathroom vent 
pipe which goes
through the roof (I don't know its technically-correct name) will work. Just 
make sure the
[antenna mounting] mast's O.D. provides a reasonable force fit into the I.D. of 
the 
bathroom vent pipe. This would probably preclude use of the Cushcraft as they 
mount over
the mast; a side-mount design such as the GAP or Hy-Gain would be needed. Is 
this worth
considering or am I playing with fire? If it is a viable alternative to the 
tripod I'd like to go that
route as I really am leery of putting up a tripod.
        Last but not least, if I do decide to ground mount any of the 
aforementioned antennas
(with the exception of the GAP), how many radials would be considered a minimum 
for
reasonable performance (rag chewing and diddling in contests)? How long should 
they be?
The 18-MHz band is my favorite for weekend phone ragchewing and 7-MHz my 
favorite for
CW ragchewing of an evening or morning (at least that's how it worked out in 
Nevada).

Thanks for the assistance.

73,
Bob AA0CY


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