Hi Carl,
> Youre welcome to your opinion based upon your experience Tom.
It is much more than experience. Good science can be proven or illustrated
through experiments and measurements. Opinions are just opinions, and have
the same value as the effort that went into confirming them.
For example, a bead does not "keep a signal inside a cable". It simply
changes the outside shield impedance. The outside of the shield, at a few
hundred kilohertz or higher, is isolated by skin depth from what the filter
affects. If we have significant or problematic outer shield currents on desk
gear, it would be much better to fix the bad cable, bad connector, or figure
out why the cabinet is behaving so poorly that unwanted currents spill over
to the outside of the cable.
There are valid applications for coaxial isolators, but they are all outside
the shack or away from the desk equipment.
> While 160 never presented any problems your rebuttal to the YCCC paper was
> generic and on 20-10 and also 6M I beg to differ based on my and others
> experiences.
Personal opinions, without reasonable technical backbone, don't mean much.
Data, or at least good logical explanation of how something works, goes a
whole lot further than opinions, guesses, or personal declarations.
You can see how a wired connector disturbs common mode sensitivity here:
http://www.w8ji.com/coaxial_cable_leakage.htm
Scroll down to Connector Mounting and you will see just an inch of open
connection to a non-chassis mounted connector on 8 feet of cable ( actually
8' 3" with that pigtail installed) increased 40-meter common mode response
by 40 dB over an 8-foot long cable routed normally.
If I had common mode ingress or egress issues on higher power RF cables in
my shack required illogical band-aids and hole plugs, I'd figure out what
was really wrong with my equipment, cables, or wiring. :-) If stuff is
built and wired correctly, there isn't even a reason to use RF grounds on a
desk. They'll make no difference at all. Neither will isolators or beads on
RF cables.
73 Tom
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