Topband: ANC-4 and MFJ-1026 Comparison

[w2pm at aol.com]

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 at gmail.com>
To: topband at 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