[Elecraft] Correction P3 Noise Gremlins

[Jim Brown]

On 12/4/2011 1:08 PM, Fred Jensen wrote:
>   A group of very narrow noise pulses, not terribly strong, run
> through the display at maybe 5 or so KHz/sec, usually from high to low
> frequency.  I might have heard them once or twice, generally there's no
> audio indication.  I disconnect my antennas when I'm not using the radio
> but leaving it on, and I've never seen them then.

Signals like this are quite common here in northern California. I don't 
know their source, don't know if they are intentionally "signals" .or 
unintentionally radiated noise.  I find that I can often hear this stuff 
in my headphones.

>
> 2.  A more broadband, bump in the reference level runs across the
> screen, maybe 20-25 KHz/sec, again usually down in frequency but not
> always.  It's definitely some sort of broadbandish signal coming in on
> the antenna.  I've never heard anything as it goes by.  I'm about 25 mi
> from Beale AFB with the PAVE PAWS radar and numerous other electronic
> systems the USAF never talks about.  I'm a bit suspicious, but it's
> certainly not a problem.

This sounds like typical trash from electronics equipment and their 
switching power supplies.  Can be anything from battery chargers to 12V 
switching PSUs for low voltage lighting to computers to various 
microprocessor-based equipment of all sorts. The fact that stuff like 
this is not audible is largely due to AGC smoothing out the increased 
noise level when we tune across it.

73, Jim K9YC