Dan,
My comments are inserted below:
> I'm planning to install a Channel Master pushup mast (with stinger on
> top)
> as a vertical antenna for 160 meters. The mast is steel, and about 2.5"
> in
> diameter at the base. It will be guyed. I have two questions:
>
>
>
> 1) What is the conventional wisdom about insulating the base of such
> a
> vertical from ground?
This works OK, provided mechanical strength is sufficient.
> How far from ground does the bottom of the mast
> have
> to be?
Low voltage point in most respects, so a large 'gap' is not required.
> What materials are best to use as the insulator?
Any material which will not breakdown under usual conditions of moisture,
dirt, UV, and RF. Included among these are: fiberglass, Delrin, Teflon,
and other synthetics.
> What materials should I avoid?
I'd avoid anything containing carbon fibers, including BLACK-colored
pieces of the above-mentioned insulators.
>
> 2) Does anyone have a specific proposal for a base insulator for
> such
> an antenna? I'm especially interested in anyone who is using such a mast
> as
> a vertical, and has real experience with the mechanical and electrical
> issues of all of this.
I used fiberglas ROD to insulate my 64' vertical TOWER for use on 80m.
It's been up and used in this manner since 1988 with NO problems.
>
>
>
> My current plan is to use a 1" piece of Delrin with a thin steel plate on
> top of it (to spread the weight/pressure) as the base insulator. What I
> don't know is whether one inch is far enough from "ground".
Not sure if I'd use a FLAT surface, as this would collect moisture, dirt,
etc ... one inch is sufficient for spacing, due to the low RF-voltage
present at that point.
>
>
>
> Thanks!
>
>
>
> ***dan, K6IF
Good luck!
Don
N8DE
>
>
>
> Don't forget the California QSO Party, coming up the first weekend of
> October!
>
> _______________________________________________
>
> See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
> Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
> any questions and ask for Sherman, W2FLA.
>
> _______________________________________________
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>
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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