[RFI] DFing an HF RFI source

Kelly Johnson n6kj.kelly at gmail.com
Mon Oct 2 19:56:41 EDT 2006

I have an RFI source in my neighborhood that I'd like to track down,
but could use some advice.

The noise source sounds like a "click" or small burst of energy at
approximately 1Hz.  In other words, I hear a burst of RFI a little
faster than once per second.  It seems to be relatively narrow band.
I don't hear it below 17 meters.  It is strongest on 17 meters, but I
can sometimes hear it on 15 meters and maybe even 10.  I've never
heard it above that.  I have DF'd the general direction using my tower
mounted HF yagi and the RFI peaks at about S7 or S8 on 17 meters which
is fairly strong, however I can't hear it when I walk the neighborhood
in that direction with my FT-817 and a whip.  I obviously can't carry
a 17 meter yagi around the neighborhood.  What other decent antenna
can I use to DF something doesn't appear to be broadband enough reach
into the VHF region?

FYI - The strength of this noise source varies from day-to-day and
some days I don't hear it at all, but it's there most of the time.

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