I'm in the process of moving this station from the arctic to
the Kenai peninsula on a hill top about a mile from the ocean.
Sunday we un-installed the Rohn 25 1/4 wave topband vert
with insulated base using the Rohn BPH25G tiltover base and
a sheet of Teflon.
After about eight years the Teflon looked fine, a little dirty
but still a good insulator and intact. I had the base covered
with a tarp and never had a failure at full smoke, summer or
winter. Mostly winter and snow however.
The top plate is spun around 180 degrees and is bolted to
the bottom plate with the Teflon in between. Four half inch
bolts are used with Teflon spacers and washers to make it
as secure as the original design.
The sheet Teflon is 1/4 inch. The spacers were cut from one
inch bar stock with a half inch hole. The sheet was cut to fit
the top plate and the end pieces were used as the washers.
I had some interest in this from my previous post and took
two pictures. The first shows the base plate in its normal
configuration with the Teflon parts. The second is the base
plate insulated. I don't have a web site but would be happy
to forward these pics to anyone.
Using the Rohn BPH25G with a sheet of Teflon to insulate
the base of a tower is probably only a good idea if you can
find one used or cheap.
73 Rich KL7RA
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