Hello Tree
I tried calling you early on, with no luck in the ARRL 160 test.
Possibly your noise was one reason you could not pick me out. Later on,
you called me while I was CQing, so all was good. I have a W8JI DXE
phasing box here, (NCC-1) and I use it to help cancel out some awful
line noise to my west. I suspect that there are many noise sources all
contributing, but I am able to improve my S/N ratio quite well with the
NCC-1. I phase two beverages aimed at 220 and 260 degrees, and feed the
output of the NCC-1 to my K3. At times I can get rid of about 10 dB of
crud. It isn't perfect, but it helps. Every day seems different, but it
usually helps most of the time. I lose when the signal is the same
heading as the noisy pole.
I am building another beverage and have hacked about 500 ft of brush
thru the woods so far. I have much more to go as I am hoping to lay out
1200 to 1500 ft of wire aimed at 290 degrees. I am hoping that it is out
of the noise direction and will be quieter and work for stations in the
far west. I have a JA wire aimed at 330 and it is quiet. I think that
290 degrees is beverage #7 and my woods are getting pretty crowded with
overhead wires. Only the west and SW wires are noisy.
Dave K1WHS
Lebanon, ME.
3. New use for Noise Canceling box (Tree)
Message: 3
Date: Sat, 3 Dec 2016 06:01:23 -0800
From: Tree <tree@kkn.net>
To: 160 <topband@contesting.com>
Subject: Topband: New use for Noise Canceling box
Message-ID:
<CAKF9Hhaqb96NW4+914g-UO1pbyfNJYZs9FR10wWxjUuRuXwUkg@mail.gmail.com>
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Last night - around 8 PM or so - this HUGE noise signal showed up on 160 -
sweeping up the band slowly. Probably a DC power supply with signals every
80 kHz or something. But - it has some energy all over the ban - thus
rasing my noise floor. Sorry if I was an alligator last night.
I put a Beverage up to the East just before the contest started - so I had
two RX antennas - the other being a Hi-Z 4 square. The Hi-Z said the noise
signal was East - perhaps a bit stronger in the South direction than North
- so call it just South of East. The Beverage picked it up very well - so
it agreed. A feeble attempt at DFing last night was unsuccessful - but
will be tried again if it stays on during the daytime. It is still on this
morning before Sunrise.
The nasty part of the noise is about the same signal strength as most good
signals coming in that are not local (looking at the band scope). It has a
10 kHz or so wide peak.
I was able to put the two RX antennas into a MFJ-1026 - with the output
going to the RX input of my K3 - and adjusted the controls to null out the
noise. With a local signal - I have been able to obtain deep nulls and
this proved to be true with this noise. I was actually running guys on the
East coast right in the middle of the worst part of the noise after doing
this.
This technique would likely be useful for those who have a similar noise
situation - so I wanted to share. You obviously don't need a beverage for
the "noise" antenna - just something that is good at picking up the noise
and perhaps nothing much else. If you have a neighbor that has a noisy
device - just put something that is close to their house.
It's a battle out there to keep your noise sources under control. I'll
report back if I am successful in finding this one.
73 Tree N6TR / K7RAT
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