Author Topic: Cable Shielding  (Read 2024 times)

Offline engelbma

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Cable Shielding
« on: May 16, 2013, 06:49:19 AM »
I'm sure the experts know this ! Still I found it informative.

http://www.youtube.com/watch?v=6HZ1C_9o3gU
"No one cares how much you know until they know how much you care"

Offline palaughton

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Re: Cable Shielding
« Reply #1 on: March 24, 2015, 01:13:23 PM »
Definitely going to try this.

Offline tangmonster

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Re: Cable Shielding
« Reply #2 on: March 27, 2015, 10:49:44 AM »
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.

Offline chipwelder

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Re: Cable Shielding
« Reply #3 on: April 08, 2015, 08:56:23 AM »
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...
OK! I've had it! I don't give anymore Kharma. Kharma should work in mysterious ways...

Offline Ampdog

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Re: Cable Shielding
« Reply #4 on: April 09, 2015, 04:24:46 AM »
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.
Audio must be the only branch of engineering where lack of basics' knowledge is considered a superior form of wisdom. (Anon)

Offline chipwelder

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Re: Cable Shielding
« Reply #5 on: April 09, 2015, 09:58:44 AM »
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...
OK! I've had it! I don't give anymore Kharma. Kharma should work in mysterious ways...

Offline chrisc

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Re: Cable Shielding
« Reply #6 on: April 09, 2015, 10:06:50 AM »
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