After nearly two years of trying to get some measurable improvement with
the MFJ-1026 noise cancelling box I finally gave up and sold them on
E-Bay and purchased a DX-Engineering NCC-1. The frustration of the
finicky controls on the MFJ was time consuming and I never was able to
realize much benefit. I decide to buy the NCC-1 with the idea of
phasing some Beverages for both noise reduction and possibly enhance
signal performance. The ability to have 360 degree control and a smooth
large knob made sense. My first test was on 160 meters with the K5P
DX-Pedition on Palmyra where I have two Beverages 900' long bur running
end to end and not staggered or spaced. Both have equal length
feed-lines to the shack. They are reversible Beverages but both were
tested in the West Direction which was spot on to K5P. Over several
hours of listening and switching I was very impressed how K5P, although
readable on a single antenna just amazingly rose from the noise level
when I would adjust the NCC-1 phase controls. It was quick, smooth, and
easy. It was repeatable for over several hours of listening and the
phase Normal/Reverse switch would make the signal disappear when thrown.
First one antenna alone and then the other antenna alone and then the
two antennas through the NCC-1. I did not expect to work this way that
well but it surpassed my expectation. Also with the tropical TS we
often receive here in the Caribbean I could make adjustments to
effective take the QRN static down to near nothing. Of course I got some
reduction before in this with just the selection of the right Beverage
but not dramatically as much. I now have added my entire bank of
beverages to the other input even though some run N/S and other NE/SW.
I will also try to see what I can get from two Beverages, One S/E and
the other S to see if i can get any improvement on VP8STI if they fire
up on 160 soon.
Also for the first time I had excellent copy on K5P on 80 meters but
they came on one hour after my S/R and i was not able to break the NA
wall calling them. Nor did I have enough time on 80 to really test the
phase on two really long Beverages. I was hoping that two Beverages,
even though not space nor staggered, but end to end, would allow for
more capture area and a better ability to null out noise from other
directions. Hopefully they will come on 80 at the Sunset and stay on
for a few hours at least to check the results.
I would imagine also that the conventionally way the NCC-1 is depicted
in the catalog with a "noise" antenna would be fine in some
circumstances to null out other random noise sources but I did not try
this yet. My only beef is that DXE offers free shipping for orders this
size to the U.S. but that means only continental U.S. even for the same
U.S.P.S. P.O. Box and Zip Code address which I have. Ironically most
North American vendors take the same approach but items on Ebay from
China, when they say "free shipping" mean it. I noticed that China Post
has a contract with Fed-Ex to take all their small parcels here and it
is super fast. But the additional shipping charges added for me are
worth every penny.
Herb Schoenbohm, KV4FZ
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