Carefully inspect the PVC element insulators where the elements clamp to the
boom. I believe they are made of PVC, and with age and UV exposure, could
have cracked when the lifting cable snapped. It's also possible that one of
the other elements sustained damage causing intermittent conditions that
interact with the 40 meter element. All of the elements are insulated from
the boom on the C-4.
In a previous post, you mentioned you were considering welding the sections
of the tower together rather than install a new cable. Instead of welding,
have you considered putting large clamps on each of the movable sections,
lifting each section with a gin pole, then clamping the bottom to keep it
from telescoping back into the larger section? That will at least give you
the option of re-cabling at some later date, not to mention making it easier
to remove the tower when the time comes.
Ron N6AHA
> 40 meter element now "hears" great, but on transmit, much
> crackling and distortion occurs, almost sounding as if RF
> arcing is occurring per fellows on the Hawaii Afternoon net
> yesterday. Don't know the innards of LMR-400, but is it
> possible it was permanently damaged in some way --
> stretch of the inner conductor, crack in it, or now the outer
> conductor is permanently pinched in toward the inner, and
> arcs. This "arcing" occurs even with only 50 watts output!
>
> I hope the problem can be solved by replacing the coax,
> and that some problem to the 40 meter dipole, unnoticed
> yesterday when all was at ground level, has not occurred.
> Visually the dipole, linear loading, matching coil, etc.,all
> appeared just fine.
--
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