In Portsmouth NH there is a little Island that I wanted to operate QRP from
called "Four Tree Island" but there was horrific static wideband noise.
I brought along my 3.5' diam. 20m Mag Loop and by rotatiing it was able
to see one possible direction where the noise might be coming from.
The little transmitting loop has deep nulls off the sides.
Walking towards a noise peak direction a 2m HT picked up the noise.
.
The noise originated at an electrical transfer station used to provide
power to the island and a call to the electrical company solved the
problem pronto. Operation from the "walk to" island now is wonderful..
.
jim / W1FMR
--- On Tue, 12/20/11, Jon Zaimes AA1K <jz73@verizon.net> wrote:
From: Jon Zaimes AA1K <jz73@verizon.net>
Subject: Re: Topband: Noise problem question
To: "W5UN" <w5un@wt.net>
Cc: topband@contesting.com
Date: Tuesday, December 20, 2011, 5:33 AM
Dave,
I use my mobile rig to track down such noises (an IC-706Mk2G with a KJ7U
160-6m screwdriver antenna and 2/440 whip). I also have a couple of
small AM and VHF-AM (aircraft band) portable radios when needed.
The closer you get to the noise, the higher in frequency you should be
be able to hear it. Sometimes I'm up to 300-400 mhz before I can zero in
on the exact pole that is the source after driving back and force in the
general area. Beam headings from the house can help with the initial
zeroing-in.
I make note of the pole number -- there are tags about eye level -- and
then notify the utility. Here I have two that overlap in this area, and
I've found the guy responsible for RFI issues in each and report it
directly to him. They usually appreciate I've done all the legwork and
get it fixed in short order.
73/Jon AA1K
www.aa1k.us
On 12/18/2011 2:36 PM, W5UN wrote:
> I'm looking for input from someone who has experienced a similar
> situation as I describe below.
>
> About 3 months ago I began experiencing severe noise on top
> band. It's a constant white noise which begins to drop off above
> 2.5 mHz, and is hardly noticeable on 80, and not there at all on 40
> meters and above. Every once and a while the noise will drop off
> completely, only to return a few minutes later. It is there about 98%
> of the time.The severity seems to vary a little, but is typically
> S9+15 db when present, and S3 during the rare times it drops out..
> This noise is coming from the eastern direction, about a mile from
> here. There are power lines.there, and these appear to be the source,
> however there are similar power lines of the same voltage here in
> other directions, including one to the southwest about 800 feet away,
> but that one has no noise. Has anyone experienced such noise as this?
> I need to see if I can track this down and get it fixed. Any help
> will be appreciated.
>
> Dave, W5UN
>
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
>
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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