[RFI] Anyone know what this might be

Kelly Johnson n6kj.kelly at gmail.com
Sun Jan 23 02:03:27 EST 2005

I DF'd the noise tonight then went out scouring the neighborhood with
my FT-817 and a whip.  I couldn't find the source.  It's S9 in a 6KHz
bandwidth in AM with my 3 element yagi aimed at the source so it's
fairly strong, but not strong enough to hear on my whip.

I recorded the noise as .wav file and put it on my website.  At first
I thought it sounded like white noise, but now I realize that it
sounds more like a motor starting up or something.  The noise lasts
about 1 second and repeats every 24 seconds. I'd love to have people
listen to it and help me identify the source.

You can find the file on my website at:

Click on the RFI-1 link near the bottom of the page.

On Sat, 22 Jan 2005 19:21:07 -0600, WX5L <wx5l at charter.net> wrote:
> First you need to get a direction of the noise. I would hope you have a
> rotatable HF beam. Carefully rotate and determine the direction of strongest
> level. Only then can you set out with your portable receiver. It seems that
> the source maybe further out than you think. You will need to set out on
> foot in this direction with your portable set on one of the frequencies with
> the noise. Clip a wire from your HF antenna to the portable so you can tune
> to a frequecy with a peak so that you can set out on foot with the portables
> receiver set.
> Randy
> WX5L
> ----- Original Message -----
> From: "Kelly Johnson" <n6kj.kelly at gmail.com>
> To: <rfi at contesting.com>
> Sent: Saturday, January 22, 2005 1:26 PM
> Subject: [RFI] Anyone know what this might be
> > I've been noticing an RFI source lately.  It sounds like a short 1
> > second blast of "white noise" which occurs at 25 or 30 second
> > intervals.  It appears to be there 24/7.  I hear it on 40 through 17
> > meters.  It peaks at about S7 or S8 in a 2.4KHz bandwidth.  That's
> > pretty strong considering that my noise level at nigh in a 2.4KHz
> > bandwidth is only about S1 or S2.  It's not strong enough for my
> > portable receiver to pick up so I've had trouble DFing it.  I have yet
> > to try to DF it with my HF yagi.
> >
> > Anyone have an idea what this may be?
> > _______________________________________________
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> > http://lists.contesting.com/mailman/listinfo/rfi

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