RE: EMP =- PULSED PHONE DESTRUCTION!

To: tesla-at-pupman-dot-com
Subject: RE: EMP =- PULSED PHONE DESTRUCTION!
From: "Payne, Will E" <will.e.payne-at-lmco-dot-com> (by way of Terry Fritz <terryf-at-verinet-dot-com>)
Date: Mon, 14 Sep 1998 17:06:47 -0600
Approved: terryf-at-verinet-dot-com

First, there is a critical difference between common mode and differential
mode power spikes.  In phone lingo these are longitudinal and transverse
modes, respectively.  Most lightning, EMP, etc and probably TC induced
stress is the longitudinal mode.

My favorite "old Indian trick" is to take a big deflection yoke core and
wind your power or phone cord thru it as many times as possible.  WORKS
GREAT and I use it to cure broadcast RFI or spike problems where filtering
and grounding efforts of others have failed.  The deflection yoke is a high
mu, low frequency ferrite formula unlike the RFI ferrite designed to
attenuate computer hash.  Deflection yokes should be great for suppressing
unwanted TC energy in the 10 kHz to 10 MHz range.

Will


> Also use a pair of "hash" chokes (12 AWG on a ferrite
> core) in each line lead.  This will surpress most all trying to enter the
> power line.
> 
> DR.RESONANCE-at-next-wave-dot-net
> 
>