There is also the: JPS ANC-4 Noise Canceller
http://www.jps.com/downloads/support/anc4man.pdf
gwatts wrote:

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


--
Joe Leikhim K4SAT
"The RFI-EMI-GUY"©

"Treason doth never prosper: what's the reason?
For if it prosper, none dare call it treason."

"Follow The Money" ;-P