[Elecraft] P3 Double-humped Noise Monster

[Roger Crofts]

I am really happy I added the P3 to my K3. It is my window on the band. I can't imagine operating without it. I have had the P3 for six months now, but just recently it has started to display two big ugly humps of noise that drift across the display. This happens on all bands, but it might not appear for 20 minutes after switch-on. The double-humped noise monster is 30-40Khz wide and about -100 dBm level. When the antenna is disconnected the signals disappear but not the double-humped monster. There is no sound in the K3, so it looks like the noise monster is being generated within the P3. The frequency of the noise monster is incredibly sensitive to almost anything I do in the shack. It even shifts frequency if I put a few sheets of paper on top of the P3. If I put a book on top of the P3, the noise monster shifts completely off the screen (even with a 200KHz width). But it will drift back again later, whereupon I can remove the book and shift it again. This is a bit inconvenient, so can anybody tell me what is going on here?

73
Roger, VK4YB