[RFI] Regular birdies

JW jwin95 at yahoo.com
Sun Oct 2 20:07:52 EDT 2016


I tracked down a "wavering carrier" I had on 160 meters to a residence 1.9 miles away to my north. This is in a city/suburban environment over relatively flat, but conductive (30 mS North Texas) earth. I make mention of this ONLY to give some idea of how far away these noise sources or signals can be! I notice you have 'humanity' (houses or homes on lots) west of you out past the airport about two miles or so distant.

I tracked two other such "carriers" to two other discrete residences to my SSW and W at about 3700 ft and 4200 ft respectively. I have been out with different gear at different times to confirm this, using different receivers (including DF receivers) as well (i.e., I can circle the block and the DF antennas continue to indicate a specific residence). These 'carriers' are also receivable in the 80 meter band.

Here is a sample of the carrier at it appears on 80 meters (it makes kind of a tea kettle whistle sound):


I think you are going to have to track this down (the 'hard', old school way) as you indicted in your previous post in order to next identify the source. 

73, Jim WB5WPA

      From: Gary Smith <Gary at ka1j.com>
 To: RFI at contesting.com 
 Sent: Sunday, October 2, 2016 5:09 PM
 Subject: Re: [RFI] Regular birdies
Unfortunately, these birdies are not from 
within this house.

I killed the power to the house, ran the 
12V equipment, the K3s and P3 from a 
battery and they still come out just as 
strong on both the vertical and the HI-Z 8 
element. There are some directions the 
HI-Z kills the birdies in. 

What is difficult for me to picture is, 
direction-wise, they seem to have a strong 
signal coming from the west but to the 
west is nothing but marsh, ocean, a 
peninsula, more salt water and finally an 
airport a couple miles away.


Since this appears to come from a power 
supply or some electronic device and most 
likely close by, I'm at a loss. My nearest 
neighbors aren't the type to let someone 
into their house to sniff the air and I'm 
not going to deal with them at this point. 
What might be a workable but expensive 
solution is to find a NCC-1 and use both 
the 8 element HI-Z and the 3 element HI-Z 
to null out the interference.

Now to see if I can find a used NCC-1 at a 
reasonable price.

The beat goes on.  



> Not really sure that I'd call them birdies 
> but here is a family photo of them seen on 
> the P3:
> http://doctorgary.net/RFI-K3s.jpg
> they are regular at 8.02 
> 3.506.07 MHz
> 3.514.09
> 3,522.12
> 3.530.14
> 8.02
> 8.03
> 8.02
> I see them with both the Inv-L and the Rx 
> antenna but much more pronounced on the 
> Inv-L
> They're not on all bands but I come across 
> this all too often. I've looked at the 
> coax connectors and all are tight. Any 
> suggestions? 
> Thanks & 73,
> Gary
> KA1J
> _______________________________________________
> RFI mailing list
> RFI at contesting.com
> http://lists.contesting.com/mailman/listinfo/rfi


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