> If ferrite isolators or beads have been determined to improve the shield
> performance of a coaxial cable in your hamshack, something is
> fundamentally wrong either with the cable (but most likely the connectors
> at either end) or the shielded enclosure(s) its connected to.
>
> I've seen literally hundreds of improperly installed PL-259, type N and
> BNC connectors. Years ago I stopped allowing anyone to bring coaxial
> cables into my shack because so many are improperly installed.
It seems Frank, Jim, myself, and many others are in exact agreement. This is
because underlying science is universally logical and valid, and proven both
by measurements and by time in thousands of commercial systems.
Because I use phono plugs that really have improper shield grounding
integrity, and sometimes the pressure connections add a tiny bit of unwanted
shield impedance to the groundplane of "the box entrance", I use high
impedance beads on these particular cables. I also, as a practice, keep an
eye on those connectors. I use those connectors by necessity, because
several of my radios use phono plugs for external antenna ports, and there
is no easy way to change connectors.
In some places, how we attach cables doesn't matter much at all. In other
places, in particular inside the hose, small errors can create large
problems. The building entrance is also critical, if we want to keep bad
things outside.
Save the isolators for outside, where they might do something meaningful.
73 Tom
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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