Cable Shielding

engelbma

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I'm sure the experts know this ! Still I found it informative.

http://www.youtube.com/watch?v=6HZ1C_9o3gU
 

tangmonster

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a bit more reading on the subject:


http://en.wikipedia.org/wiki/Faraday_cage

A shield needs to be grounded though at least at one point.
 

chipwelder

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Well that was an unconnected rca... I do suspect it would not be so very responsive if actually plugged into a source... not saying he speaks rubbish, just saying be real...
 

Ampdog

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He was demonstrating the principle, probably in such a way that the scope display would be easily visible. I tried to read the Y-axis setting but could not. A good demo would be to display a dual trace demonstrating the difference between an unshielded cable and a shielded model.
 

chipwelder

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Agreed, I just think of how susceptible my little twisted pair two strands of RG59 is when unplugged vs plugged in... I think that constitutes a failure mode though... if unplugged everything will swamp the signal...
 

chrisc

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You cannot tell what the oscilloscope was reading.  Was it millivolts, microvolts or what?  With no termination, it is bound to pick up induced voltages
 
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