[Elecraft] K3 weird noise generation...??

[Matt Zilmer]

Next time you see something like this, take a look at the VCO control
voltage (PLL1 or PLL2) using the DISP meter function.  If the K3 goes
out of lock, it puts out all sorts of garbage audio and the PLL (VCO)
voltage moves around randomly.  

I've had this happen on 5 MHz when working with certain MARS
frequencies.  I've found it *only* happens when a command sequence
comes from RMS Express - something that puts the K3 in a weird mode
(probably commands too close back to back).  I haven't determined what
the command sequence is yet.

If this is what's happening, you probably should discuss it with
Elecraft support.

GL & 73,
matt W6NIA

On Thu, 30 Dec 2010 16:41:23 -0800, you wrote:

>I came home from work and turned on the K3 and the P3 and then switched to the CW zone of the 40 meter band. The VFO was about 7.009 as left from my last visit yesterday.  I turned the VFO up just a tiny bit and this strong, like S9+ broadband noise came through.  Funny because I remember looking at the spectrum of the P3 and I did not see anything there.
>
>A long story short.  I discovered that this noise was being generated by the K3.  I had checked the band with my Icom 756 Pro III and nothing was there except lots of CW signals.  I tuned the Pro III around the same spots as the K3.  So, I rotated the VFO slow up frequency from 7.009 and at 7.00945 the noise started and continued up to about 7015.5.  Now, on the spectrum this was a good 50 dB over and above my normal noise floor (sorry, not sure if I am using the right terminology) and it was the same across the entire spectrum which by the way was set wider then this frequency range of 7009 to 7015.  And, all other CW signals disappeared and many of them were stronger then this noise level.
>
>So, if I turned the VFO just past the upper threshold of 7015.5, the noise disappears entirely and there is nothing but normal display of CW signals on the spectrum.
>
>I then decided to power off the K3 and P3.  Powered back up and this weird noise phenomena disappeared.  Now, the K3 and P3 is acting normal.
>
>Anyone see anything like this?
>
>73, phil, K7PEH
>K3 Serial #3799
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