IS this really true or is it possible
that a common mode signal is generated equally
on both of the twisted wires instead of possibly
a phase shifted differtential signal ??

Amplifiers are designed to reject common mode signals
unless you desire a very big voltage input.
Like +/- 100V

???


In my opinion nothing beats the old russian doll idea
where you nest two or three layers of 100% shields.
But doing that right that is very expensive and not easy to do.
You need to deal with ANY/ALL wires which
may breach the shielding. And any wavelengths of RFI
smaller than any holes can get in too.


----- Original Message ----- 
From: "George Bush" 
To: ; "PSN-Postlist" 
Sent: Thursday, May 13, 2010 8:04 AM
Subject: Re: Electronic noise


Jón-

The Cat-5 cable is twisted and therefore cancels
magnetically-induced noise (one twist acts like a
small inductive loop, but then the next twist
detects the fields backward and cancels the
noise).



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