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Old January 17th 08, 10:22 PM posted to rec.radio.amateur.equipment
gwatts gwatts is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 120
Default Noise reduction boxes

Harold E. Johnson wrote:
In the beginning, long long ago, there was a guy living on the Isle of Man
who designed a noise reduction box that worked by using a small sense
antenna to pick up more noise than signal and phasing it to cancel the noise
coming in on the "real" antenna.

This was reverse engineered by Doug DeMaw, who wound up making a little PC
Board to do this job and selling a few of them. Coming into the present
century, MFJ made a similar package and marketed it, but apparently no
longer does. (Or else they hide it in their catalog very well).

If anyone can tell me their part number of that unit, I'd be forever
indebted, and would venture forth and try to locate one to give to a friend
in Wales who is currently suffering the demise of his top band operation due
to local interference. Better yet, if anyone reading this has one that
they'd like to part with for money, I'd like to be introduced.

Regards
W4ZCB



Here's an MFJ version,
http://www.mfjenterprises.com/Produc...uctid=MFJ-1026

I have a Timewave ANC-4,
http://www.timewave.com/support/ANC-4/anc4.html

I don't know how the two compare but I'm satisfied with the ANC-4, it
doesn't completely null the noise but it makes a big difference in how
well I can copy. I use a 20' piece of wire for the sense antenna.


Good luck to your friend, best wishes to you,
Galen, W8LNA