Nice work and good comparisons. However I think it's important to note
that noise nulling effectiveness is subject to local conditions which
encorporate TONS of variables, and variables of variables. I have also
observed the ANC-4 to be easier to null, WHEN you can get a null and
the MFJ difficult, and frustrating, but you can often find a null after
all the work and it's deep and effective. But not always. There are
times the MFJ can't. The fixed gain of the noise input on the ANC4 I
found to be the largest problem with that unit which prevented find a
null (where the MFJ can) and the "fix" to that was an attenuator on the
noise input. WHen I did that, I often achieved a null after-all.
Sometimes as good as the MFJ, sometimes not quite as good. But then
the complexity of the tuning increased on the ANC4. Conversely, I have
found the noise level on the MFJ to be too low at times, and run a
switched noise pre-amp on it which I sometimes need to use. Consider
that I have 4 to 6 noise antennas out there in any given season
switching through each to get the best effect, regardless of the unit.
After I put in most of the 8JI mods in the MFJ, it became consistently
better than the ANC4 on 160. Not so much so on the higher bands where
the ANC4 was as-effective most of the time.
For a relatively small station here, my noise abatement systems and
"infrastructure" is quite complex. Multiple receive antennas, multiple
noise antennas, multiple noise nullers, several complex switches and
LOTS AND LOTS of cables, wires, adapters and connectors. I love it..
Keeps me off the streets.
Pete W2PM
-----Original Message-----
From: Markus Hansen <mkve7ca@gmail.com>
To: topband@contesting.com
Sent: Fri, Dec 11, 2009 6:23 pm
Subject: Topband: ANC-4 and MFJ-1026 Comparison
During the last six months I have been comparing the relative
effectiveness
of the ANC-4 and MFJ-1026 Noise Cancellers. I built a simple relay
operated
switching circuit so I could instantly change from one unit to the
other in
order to measure the difference between the two units when listening to
real
live interference, ie. noise, TV birdies etc.
The results of my tests and oberservations are on my web site at:
http://www.shelbrook.com/~ve7ca/Ant160.htm
--
Markus Hansen
VE7CA, North Vancouver, BC CANADA
Web site: http://www.shelbrook.com/~ve7ca/
_______________________________________________
160 meters is a serious band, it should be treated with respect. - TF4M
_______________________________________________
160 meters is a serious band, it should be treated with respect. - TF4M
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