[1000mp] Mark-V and noise phasing filter (MFJ-1026, etc.)

[Ron Walters]

George,

I also about a year and half ago started having noise problems on 160-80 
and 40 meters in the evenings only, sun-set to sun-rise.  Have tried 
unsuccessfully to tracking it down, so I bought the MFJ-1026 over the 
other popular noise canceling device from Timewave.

The noise I have experienced is birdies every 17 KC on 160-80 and 40 
with signal strength decreasing as we go up in frequency

I use it with a FT1000MP connected between aux antenna and antenna out 
on the FT, don t have to worry about blowing the MFJ that way, still 
always the possibility of hurting the FT though. 

Observations,

1.  You will need an external antenna , I found the internal antenna to 
worthless for my noise issue.

I use a forty meter dipole to fight the noise, my main antenna is a 
double extended center feed zepp at 65 feet used for 160-80-40 and 30 
meters.  The zepp runs east to west, the dipole runs N to S and thats 
one problem I have, I do not have the yard or supports to keep the 
antennas apart as far as I want if I run it E to W as the Zepp.  The 40 
meter dipole is up about 20 feet.

On 40 meters I can null out noise as load as S-9 down to, S-0,  I cant 
hear it! Only drawback is the need to lower the over-all gain of the 
receiving antennas to accomplish the null, I lost about 1 1/2 S units 
comparing direct to the Zepp verses using the MFJ.  I could if need get 
the same S-meter reading but then the noise would be still in there but 
at a reduce level.

On 30 meters I do not need it.

ON 80 Meters I can reduce the noise by anywhere from 6 to 8 S-units, 
however, again I have to use a lower setting and lose about 2-3 S Units, 
thats worth it getting rid of the noise.

On 160 meters the reduction is not as great as I would like, a larger 
canceling antenna other than the 40 meter antenna would preform better 
for 80 and 160.

2.  The MFJ creates some of its own noise (Birdies) that are 
significant, I have noticed two on each band, as example on 80 meters I 
have one around 3580 and 3804 plus or minus a few and at a S meter 
reading of S-9, this only occurs when you use the internal preamp on the 
auxiliary antenna input, on 80 and 160 I have to use it since the 40 
meter antenna does not have the pickup to help cancel out the 160 or 80 
meter noise.  On 40 meters I do not need the pre-amp.

Her is some other sites with comments at the following, they are: 
http://www.va3cr.net/settings%20and%20troubleshooting/anc4.html (MFJ-ANC)
and http://www.eham.net/reviews/detail/1138 (ANC reviews) that also 
apply to the MFJ as regards to the canceling antenna.

The MFJ reviews can be seen at  http://www.eham.net/reviews/detail/1205

I think the real question you want is would I buy it again, answer is 
probably, it works, does it works a good as the Timewave ANC-4, I cant 
answer that but I would like to try one out and compare the results here 
at this QTH.

Regardless of which one you purchase it should help, will it totally 
eliminate the noise? Possibly, if not with a significant reduction.

The consensus seems to be that an external antenna is needed for either 
unit.

Ron W4LDE


George VE3YV wrote:

> I live in the centre of the city on 4.5m (15.5') wide lot.  Antennas 
> are F12 C3S on the roof (parked carefully) and trapped dipole for 
> 30/40/80.  Always have had challenges with noise sources - HI.  Recent 
> new source has pushed noise level up again -  rough when now focusing 
> on 80m for 8B DXCC.  Am considering buying a MFJ-1026 (the local ham 
> store has a sale this week) to try to kill or cope with the noise.  
> While I've read the MFJ manual (PDF on their web site), W8JI's write 
> up on his web site, and also the notes on VA3CR's web site, still left 
> with two questions:
>
> 1.  is this worth trying out? (yes I know - it depends - looking for 
> some experience)
> 2.  will it handle the 200W out of the Mark-V?
> One note - the roofing filter did help cut down some the the crud from 
> signals modulating the noise blanker.
>
> Any suggestions, tips would be appreciated.  If answers are off list, 
> I'll post a summary.
>
> Happy New Year!  tnx  73,
>
> George  VE3YV / K8HI
>
>
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