Some switching power supplies are frequency-jittered to spread their
spectrum and enable their host devices to meet FCC or Industry Canada
line-conducted emissions limits. Also some of the newer lighting devices and
cicuits can produce RF!! Y ou might try walking your neighborhood with a
portable receiver and see if you can "sniff" it out. My bet is a switching
power suppl y, based on your description. Good luck!
73,
Charlie, K4OTV
-----Original Message-----
From: Topband [mailto:topband-bounces@contesting.com] On Behalf Of Bill
Cromwell
Sent: Saturday, November 09, 2013 5:44 PM
To: topband@contesting.com
Subject: Re: Topband: Local noise source identification
On 11/09/2013 05:15 PM, Rick ve3mm wrote:
> I am looking for suggestions to help identify a local noise that I am
> experiencing on topband.
>
> It's characteristics are;
> - bandwidth approximately 15 kHz
> - amplitude relatively constant
> - centre frequency seems to vary in small steps over time, no real
pattern.
> - right now the centre frequency is 1819 kHz, it moves up and down up
> to 7 or 8 kHz.
> - does not seem to be present during the day. At least not this afternoon.
>
> I shut down all of the circuits in my house other than my shack and it
> did not disappear.
>
> Has anyone experienced something similar?
>
> 73
>
> Rick ve3mm
> _________________
> Topband Reflector
>
Hi,
I live in a four season "resort and recreation area". Many of the
'neighbors' live far, far away and come here for short weekennds, long
weekends, holidays , and vacations. When the population goes way up, mostly
on the weekends, the intruding noises are almost sure to increase. Sometimes
they wipe out parts of several bands and may last the entire "vacataion'.
Often, all or some of the interfering junk quiets when the visitors go to
bed. I have been seeting up to operate on battery power during power
outages. It's amazing how quiet the bands get when *THAT* happens <evil
grin>.
Short answer - yes - I have a signal just like that here. Probably a few
others too. Ain't it wondeful?
73,
Bill KU8H
_________________
Topband Reflector
_________________
Topband Reflector
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