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Old January 17th 08, 11:16 PM posted to rec.radio.amateur.equipment
tomtone tomtone is offline
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First recorded activity by RadioBanter: Dec 2007
Posts: 3
Default Noise reduction boxes

On Thu, 17 Jan 2008 21:52:02 GMT, "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



you didn't say what freqs you wanted it for ........... the JPS ANC-4
works between 500 khz to 80 mhz.

I 've used several of these from time to time and they work only "
somewhat " OK. when tuned to eliminate severe noise , they will
reduce or clip the signal as well. I think you will feel they are a
bit pricy for what they deliver .........

http://cgi.ebay.com/ws/eBayISAPI.dll...m=250206796968


just my experience with these ...........