> I don't see it quite that way; I'm sure others may not
> either. This opening seems quite dismissive of an actual,
> bona-fide observation I made without providing any
suitable
> explanation for said observation.
I clearly said I'm sure it can happen. I never said it
couldn't, so I never dismissed anything.
My actual statement was that I've never seen a case where
wiggling the shield in any system I've worked on caused
noise. Which I followed with a statement that it certainly
could happen when a shield was tarnished or otherwise lost
contact between multiple strand lays in the cable. It does
not happen in good cables.
So we are actually not in disagreement, nor did I "dismiss"
your results. I actually agreed with them.
As I said:
> > seen the effect you describe, I'm certain it can happen
if
> > the shield is tarnished or if the lays are not compacted
to
> > make good connections. I know that climbing past a
repeater
> > antenna with metal tools or even car keys rubbing will
noise
> > up a repeater while it is transmitting.
> >
> > This has little to nothing to do with Ray's problem,
which
> It has, according to me reading, everything to do with
Ray's
> problem in his matcher (may a re-read of his original post
> is in order?); to wit, "high circulating tank circuit
currents on
> old braided cable" - I see this as QUITE a recipe for a
mixing/
> intermodulating environment.
Sorry Jim, I disagree that is the crux of Ray's problems.
While woven shields that are not making good lay-to-lay
contact are problematic at modest to high current levels in
duplex system, my understanding is he had a "noise problem"
in a receive-only case. You can't have high circulating
currents without a transmitter active. A repeater or duplex
system is of course a VERY different case.
It sounds to me like Ray is perturbing multiple things in a
system that has some other problem he is missing, and
through enough changes eventually reached a solution. If
wall warts and other things like cable grounds are changing
noise levels, it's a pretty good indicator the system has
some major problems other than ground loops.
That's my only point. I'm not even saying he didn't need to
get rid of the old braid in his tuner, I suppose in a very
special case it could cause problems. But not normally.
When doing things like using a common power supply to
replace wall warts has an effect on system noise, it is a
BIG red flag of other problems that were missed in the
system.
73 Tom
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