I agree with Tom.
I bring my feedline away from the mast at a right angle to the mast to the eve
of my
house on a messanger line which also acts like a guy line at the top of the
small
diameter mast.
Chris opr VE7HCB
> > > I'm trying to elevate my very low dipole that is fed
> with balanced line.
> > > I'm trying to go with a non-metallic support so the
> balanced line does not
> > > interact. My dipole is currently 18' in the air.
>
> Why? Just keep the line a half foot or so from metal and it
> will be fine for many feet of parallel distance.
>
> With a low dipole over dirt, I doubt the antenna (and
> feedline) is that well balanced anyway.
>
> > > I checked around and one of the local deck builders says
> I need to put
> > about
> > > 4' of the redwood 4x4 into the concrete. That would
> reduce my effective
> > > height of the 4x4 to 16'. If I overlap the fiberglass
> mast a foot or two,
>
> I'd bet the 4x4 would snap long before the concrete moved
> even with two feet of concrete. Here in my Georgia clay, a
> good 4X4 will break before tightly packed soil will yield
> with only a two foot deep hole. I'd bet the mast would break
> long before anything else.
>
> > > have 16' + 20' = 36' which is roughly double the height
> I have now.
> > >
> > > What do you guys think about the 4' of 4x4 into the
> ground. Too much, too
> > > little, just right? I noticed that you can put l-bolts
> into the concrete
> > > footer and mount a u-shaped bracket on top of the footer
> that will accept
> > > the 4x4. This is advertised for deck applications and I
> think it wouldn't
> > > support 20 feet of 4x4. However, it would give me four
> more feet of
> > height
>
> The bending load would be far too high on the plate. I do
> this stuff all the time to support small verticals and such.
> I bore a hole two or three feet deep and slowly backfill and
> tamp the soil as I install it. I use neither stone or
> concrete. If I had loose soil, I'd probably use concrete to
> expand the diameter of the pole or make a wider base tripod.
>
> I can't imagine a non-conductive pole being any real
> advantage.
>
> 73 Tom
>
>
> _______________________________________________
>
> 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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