Hi Bill:
All 4 of my staggered beverage pairs are phased with the NCC-1. This is my
second season with the system.
Each beverage in the pair has its own coax line to the shack and is phased
with the NCC-1. Actually, there are only two lines to the shack, and each
wire is relay switched in the field.
I also use a stable "local" source using a homebrew 1.843mHz oscillator
circuit located behind each pair, and can achieve incredible nulls......from
s-9 +20 to almost zero. I use this "tune-up" method to mark out the
controls on the NCC-1 for approximate settings....both phase and gain.
On air, I will often use N7UA, N6TR or W7LR who vary, but are close to off
the rear off my EU pair and W1AW which is almost off the back of the JA
pair. It seems to depend on conditions, but the null is NEVER quite as deep
and complete as using the local source. On some evenings, I suspect because
of wave-angle arrival the nulls can be very poor, but on other nights they
are exceptional....from S-9+10 to S-3 or 4.
Prior to the NCC-1 I was also using a "fully modified" MFJ unit, and did not
notice any big difference regarding null or pattern development between
units. The biggest difference with the NCC-1 is it has a noticeably lower
noise floor.
My city QTH is a compromise location for Beverages, and therefore, each pair
is very irregular. The wires in a pair although will follow the same
"general direction" often change in height and spacing along their length
(depending on tree location), and therefore could not be considered
"identical". I think this is where using a phase box in the shack is
superior to field phasing the pair in the traditional end-fire (cross-fire)
method. The ability to adjust (correct) the gain (current) on each wire to
maximize the pattern is essential. I'm pretty sure if I phased any one of
my pair "as per the book" in the field, the pattern would be rather poor
because of the variability between each wire.
It is also very nice to be able to adjust the phase in the shack to move the
null around as needed. . Sometimes, I will need to rotate the null to
remove a local man-made noise, and I have the ability to phase ANY of my 8
wires together....not just the pairs, which then can be a very effective
noise cancelling effect.
I also use the NCC-1 to phase together each element of my 80m Yagi at 100'
to yield a rotatable 160m RX yagi. Surprisingly, this models rather well
and on air performs well. There are times when it will out-copy the
beverages, but most of the time is slightly behind or equal....probably
depending on arrival angle since the wave angle is much higher using dipole
elements this low.
73, de steve VE6WZ
http://www.qsl.net/ve6wz
> If anyone is using an NCC-1 **with Beverages** (i.e. not
> verticals), I'm especially interested in how much rejection you can
> achieve on real signals?
>
> 73,
> Bill W4ZV
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160 meters is a serious band, it should be treated with respect. - TF4M
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