> > 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
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