[RFI] Pulse noise on 40

[Gary Smith]

Cheapo caliber electric blanket maybe?
Gary...wa6fgi
  ----- Original Message ----- 
  From: K8RI (Roger) 
  To: rfi at contesting.com 
  Sent: Tuesday, January 18, 2011 8:28 PM
  Subject: [RFI] Pulse noise on 40


  The past couple of nights at various times between 10:00PM and 4:00 AM 
  I've heard a pulse noise that sounds like an electric fence *except* it 
  is more or less a discrete frequency about 3  to 6 Khz wide.  It was 
  slowly drifting upwards at a rate just fast enough to hear the pitch 
  change. OTOH it didn't take much over 10-15 seconds for it to move clear 
  through the receiver bandpass. This was a pulse with a repetition rate 
  of about 1 Hz on and 1 Hz off.  It would come and go abruptly. It might 
  only be present for a few seconds or a couple of minutes.  Signal 
  strength varied from down in the noise to a max of about S5. There were 
  extended times (half hour or more) where I didn't hear it at all.

  It did not appear to be stable enough to be a regular transmission and 
  unlike most timed noise sources such as electric blankets, heating pads, 
  and electric fences it was a discrete signal and not just broadband 
  noise.  It really didn't sound like any over the horizon RADAR I've 
  heard before. I heard it mainly  between 7.170 and 7.190, but I think it 
  was present over most of the band at one time or another.  On several 
  occasions it sounded like it was turned off in the middle of a pulse.

  Any thoughts?

  73

  Roger (K8RI)
  _______________________________________________
  RFI mailing list
  RFI at contesting.com
  http://lists.contesting.com/mailman/listinfo/rfi