Adam, the short answer is that, by grounding the shield at both ends
you have created a transformer wherein the current flow in the shield my
induce a voltage in the center conductor, and visa-versa. This is also
known as a GROUND LOOP. In many circuits where the signal levels very
low this may create problems including, but not limited to, noise and
oscillation and in general unexpected results. Remember that "GROUND IS
RELATIVE" and what is considered ground here may be a number of
millivolts different a couple of inches away. Hope this helps rather
than confuses..
73
-- Roger B. Whitaker K9LJB"Madness takes its toll. Please have exact change."
Home page: http://www.cityscape.net/~whitaker/
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