> I have been able to get away with
> using a common ground system and
> match transformers for multiple
> beverages emanating from one point.
> (I switch on the high-Z side).
My dislike for doing that comes from years of measuring relays and
switching systems. I think people would be amazed at how poor some
relays are, and some layouts.
While a reasonable RF layout will minimize crosstalk, it is far too
easy for people who do not work with RF to miss something.
The bad part is unless we measure the system in a controlled
environment, we might not be aware of any problems magnitude.
Better to be safe in a case like this, because the cost and time
difference and inconvenience between low Z switching and high Z
switching is minimal, plus it helps make sure common grounds are
avoided. Too many who work in RF daily do not understand RF layouts,
let alone casual builders.
Metal poles, mistermination, sloping wire ends, and other things we
needlessly worry about are immeasurable in the final results but
crosstalk, common mode, and ground loops are well documented and
easily measurable and calculated.73, Tom W8JI
W8JI@contesting.com
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