Hi Mike,
> I'm in full agreement with this, unless we consider our shack computer
> part
> of our "gear". :-)
The context of this was entirely "transmitter" RF cables, which also are
used at times for receiving, and devices connected in the transmitting
feedlines on the desk. The difference with coaxial transmitter and amplifier
feedlines, and RF ports on other well-designed RF accessories, is the ports
and cables contain signals inside. If transmitter system connectors or
cables "leak" or carry common mode, it is very abnormal. It strongly
indicastes a problem that should be located and corrected.
Other accessories can be different. While **cases** generally should be
common to the rest of stuff, not necessarily so for leads exiting through
poorly implemented ports. This would include many things along with
computers, like switching supplies, which might need isolation on some leads
due to poor port system design.
> I also have a split core around my keyboard cable, to keep it from
> radiating RFI.
That's a little odd. On low bands, keyboards have a very high common mode
impedance. They can't drive the cable very hard with common mode, so few
beads don't generally do much on lower frequencies. They add a few hundred
ohms in series with a CM path already in the many k-ohms. They can and do
have large differential mode currents, but not common mode, on low bands. On
upper HF through VHF, especially with hand capacitance, they can drive the
cable pretty hard.
Are you sure you don't have a receiver system "leak" exaggerating problems?
Maybe a bad box connector mounting method (like a plastic box with wires
from RF connectors) or other RX system issues?
73 Tom
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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