[Elecraft] Correction P3 Noise Gremlins

[Fred Jensen]

On 12/4/2011 11:09 AM, Phil Theis wrote:
> I am talking about noise gremlins that move slowly across the P3
> I know that it could be generated by a Power Supply but I inadvertently
> called the P3 a PS.

No problem, I knew you meant P3, "S" and "3" are moderately close on the 
keyboard.

Regarding the "noise gremlins":

What do they look like?
Are they sort of broad-bandish [a technical term]?
How fast do the gremlins move? [KHz/sec or something like that]
Where do you set your Ref Lvl?
What is the Scale setting?

Occasionally, I'll see:

1.  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.

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.

3.  Right after P3 build, my baseline would "wander" upwards as if there 
was an increase in noise in some range on the screen.  I heard nothing 
as this happened.  Putting my hand flat on top of the P3 restored the 
straight baseline.  Taking the case apart and shining up the 
paint-masked places where the screws go and making sure all the screws 
are tight seems to have fixed it.

It seems the entire radio spectrum is suffused with man-made signals of 
all types.  Try listening on 443.920 for awhile.  Many of the noises 
there would get a little boy in trouble if he made them. :-)

73,

Fred K6DGW
- Northern California Contest Club
- CU in the 2012 Cal QSO Party 6-7 Oct 2012
- www.cqp.org