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Old June 28th 04, 10:27 AM
BDK
 
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In article telamon_spamshield-39A0DB.00324028062004
@news.sf.sbcglobal.net, lid
says...
In article ,
John Doty wrote:

Telamon wrote:

Snip

This claim is widely made in the hobbyist literature, but I've never
seen any measurements to back it up. I've tried to check it myself,
and found the opposite: close to modern sources of EMI, the field
tends to be predominantly magnetic. You have to be very close the
source to see any effect at all: beyond ~0.1 wavelength induction
balances the field pretty effectively.


First off I did not realize this was cross posted so this is my last
post to this thread.

I'm not not regurgitating hobbyist claims but my experience in this
matter. Although 0.1 wavelength is more than enough to cover a urban
lot and your neighbor at short wave frequencies theory does not do
justice to a non homogenous environment we all live in. Most electronic
noise generators do not have efficient antennas attached to them where
the environment easily distorts the electric fields. I have repeatedly
experienced predominantly voltage common mode coupling of local noise
sources. Without exception mitigation methods against voltage common
mode noise were always successful and current mode antennas always
picked up less local noise.



My main problems with noise have been the next door neighbors dimmer and
the transformer that threw out hash galore and took the electric company
about 2 years to fix. When it rained, or was cold enough for dew to
form, it was like a really annoying buzzer from about 0 to 10 MHZ. I was
overjoyed the night it blew up. It was "on the list" due to my nagging
them, but lightning did the job...

BDK