[RFI] More on 160 M RFI - significance of hum bands

[JW]

Pete,

Sounds like the perfect job for my first choice in low-band noise DF work, the "Coastal Navigator" RDF receiver as shown here. 

https://powerlinenoiseallentexas.wordpress.com/df-equipment/


I have used a unit such as this to successfully DF and locate several different 'noise' sources in my area over the past several years. With practice and technique, I have located sources down to a particular house or power pole.


de Jim WB5WPA

      From: Pete Smith N4ZR <n4zr at comcast.net>
 To: RFI List <rfi at contesting.com> 
 Sent: Wednesday, March 29, 2017 7:27 PM
 Subject: [RFI] More on 160 M RFI - significance of hum bands
   
I'm having more trouble than I expected localizing my power-line 
interference. In particular, one component of the interference varies 
from almost negligible to whopping big, as visualized on HDSDR, and 
often appears in wide bands 22 KHz apart..  See the Dropbox link 
<https://www.dropbox.com/s/qaxt7qnyl51hnp3/hum%20bars.png?dl=0> for a 
visual.  You can see the hum every 120 Hz on the audio display - when I 
move the AM passband away from the hum bands, the 120-Hx 
multiplesessentially disappear.  The bands themself vary, without 
apparent pattern, from very strong - as seen in the illustration- to 
invisblle/inaudible. Just now, they stuttered a few times and then 
disappeared from the waterfall (and the audio) entirely, in the course 
of a few seconds.  With the AM passband in one of the hum bands, the 
base noise level is about S9; without them, it is S7, which still isn't 
great, but worst things first.

Really puzzling - any advice on what I'm seeing and how to track it down 
will be much appreciated.


-- 

73, Pete N4ZR
Check out the Reverse Beacon Network
at <http://reversebeacon.net>, now
spotting RTTY activity worldwide.
For spots, please use your favorite
"retail" DX cluster.

_______________________________________________
RFI mailing list
RFI at contesting.com
http://lists.contesting.com/mailman/listinfo/rfi