[Lowfer] What is this ?

[rick kirby]

Hi All;
 Ive had Spectrum Lab and an active whip sitting on the Watering Hole (185.3) for a few days and Im getting lots of wavy noise that goes up and down in frequency and amplitude.It looks like a distorted sine wave sort of.. Ive inckuded a link if It works. Could it be PLC junk?

http://ka2pbo.com/captures/capt704.jpg

  Thanks
           Rick
  KA2PBO
                "PBO" 187.2 KHZ QRSS60