My location is a small rural hilltop near Charleston WV. Although it is
electrically quiet much of the time, the location is surrounded by HV power
lines for 360 degrees, some of which are within 200'. Several of these power
lines run within the woods and receive little maintenance from the utility.
Power line noise can be problematic at times and is typically worse on the
higher bands. To help deal with this noise, I was using an MFJ-1026 Noise
Canceling Signal Enhancer.
A recent post by K3LR on the Topband reflector discussed how his multi-multi
contest station was using a DXE NCC-1 to phase low band receive antennas for
enhanced performance. The description of the NCC-1 indicated that it was
similar in principle to the MFJ-1026 but was a much higher quality unit with
more features and adjustment range.
Having recently commissioned a Hi Z Triangle rx array for the low bands on my
hillside, it occurred to me that perhaps it would be effective to add another
receive antenna and phase it with the Hi Z array using an NCC-1. The system
could also be used for noise canceling as with the MFJ 1026. My early
Christmas present was a DXE NCC-1.
After the NCC-1 arrived, a day or two was taken to consider the optimum hookup
here. It quickly became apparent that I could use the NCC-1 to phase the Hi Z
triangle against one of my four 160 inverted L's or any of the other TX
antennas by taking the rx OUTPUT from the Yaesu 5K and feeding it into the DXE
box as a receive antenna. The rx output on the 5K is simply a feedthrough of
the main tx antenna while the unit is receiving. The results for noise
reduction and signal enhancement have been great and so far I have not used the
NCC-1 with two receive antennas.
Each of my four xmit L's is located on a different quadrant of the hillside to
face NE/SE/NW/SW. These use ground slope and blocking features of the terrain
to enhance performance in favored directions and have been fair rx antennas.
I was anxious to phase the Hi Z Triangle against the inverted L's hoping to
achieve some level of background noise reduction and hopefully some signal
enhancement which would aid in weak signal copying.
Out of the box, without being familiar with adjusting the NCC-1, I could
balance the antennas and get a signal peak or a noise reduction. It was kind
of intuitive how it worked. The unit is big and well made. The main phasing
adjustment knob has a good feel and is the size of a transceiver tuning knob.
Smooth. The switches have a great feel. The unit is well made and heavy.
More importantly, I immediately felt it was enhancing my receiving capability
on 160 with the antennas as described. The first night there was a light trace
of power line noise that did not move the S meter, but it was annoying and
could mask weak signals. The NCC-1 took the noise out. I was very encouraged.
The combination of the Hi Z and the 160 inverted L's always deals with any
power line noise if both antennas hear the noise, which is usually the case.
The degree of signal enhancement possible with the phasing adjustment depends
on the direction of the signal and which inverted L is selected. A combination
that worked well was HS0ZKX from the SW using the SW L and the Triangle.
Another was FT5ZM from E using the SE L and Triangle. The NE L and NW L are
less effective on signal enhancement because of the spacing between antennas I
suspect, but they work for power line noise reduction.
When I have power line noise on the hi bands, even S9 plus noise, the NCC-1
takes it out using the transmit yagi and the Hi Z Triangle as the noise
antenna. This combination is frequently used to work DX that would otherwise
be buried in power lin noise.
My long term plan remains to phase the Hi Z Triangle with another receive
antenna, probably another vertical array. The cold snowy weather has delayed
any antenna work on my hillside.
I consider the NCC-1 to be one of the best accessories ever purchased here. In
fact, it is already essential to my station operation.
73 Charlie N8RR
For simple noise reduction, I think the MFJ is fine. For phasing antennas and
ease/repeatability of adjustment, the NCC-1 is in a different league. Everyone
would not have a need for this box, but for serious low band DXing if one has
multiple antennas and/or some significant powerline problems, it will help. At
$600 it is not cheap. Wish I would have discovered this thing a few years
ago!
Now I have to decide if it will be necessary to add another Hi Z. Maybe not.
I might even put up a couple of short parallel beverages and phase those.
Guys, I love this stuff! Working the HS0 on 160 LP has rekindled my
enthusiasm, if it ever waned!
73 Charlie N8RR
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