[Elecraft] K2 VCO Alignment only 0.02V @ R30

[Don Wilhelm]

Jeremy,

5.029 volts at U4 pin 13 means that the PLL synthesizer IC is working.  
Remember that the manual voltages are for a properly working K2 that has 
the PLL IC in lock with the VFO frequency.  Your voltage only indicates 
an out of lock condition.

What is the R30 voltage now with that 5.029 volts at U4 pin 13?  You 
should now have some voltage there.  Can you adjust that voltage with 
L30?  If so, you should now be able to get everything within the normal 
range.

If you are still seeing zero volts at the left side of R30, then U6B or 
its components is at fault, not U4.

73,
Don W3FPR


On 2/3/2013 8:31 PM, JeremyJones wrote:
> So I really thing that U4 is faulty. It's putting out 5.029V on pin13 when
> that should only be 4V. All the components surrounding it seem to have the
> correct voltages according to the manual.  I think I'll replace that and see
> how things look after.
>