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Old 07-01-2008, 11:40 AM   #12 (permalink)
Tirefryr
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Quote:
Originally Posted by Megalomaniac View Post
you are wrong and have been misinformed, sorry.

The RCA connector has two parts, the center pin (signal) and the outer shell/body (ground). The outer shell/body is connected to either chassis ground, signal ground or both. Some units isolate signal and chassis ground with resistors or a transformer (that is why you can get different meter readings with amplifiers) to lower noise, but it is still a ground. And for a shield, any shield no matter how constructed, it needs to be tied to ground somewhere to dissipate the EMI (Electro-Magnetc Interference) currents that have been induced on the shield BEFORE they are coupled to the signal carring conductors

That would explain why I do not get a reading, but if that is the case, aren't you inducing noise when using a grounded shield? They go through the trouble to isolate the signal ground from the chassis, so why re-introduce one?

I don't know much about electronics, so help me out here. I know when I built motor control panels and Cell phone buildings, there were certain shielded cables that did not get grounded on either end for fear of inducing noise back through the shield. I do know you have to isolate AC from DC and high from low voltage.
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