[Elecraft] K2 PLL range test fails

[Don Wilhelm]

Mike,

Record your current filter settings and other menu settings, and then do 
  a Master Reset (hold the 4, 5 and 6 buttons in while powering on).

There is a convenient form to record the menu settings in the K2 A to B 
instructions which you can download from the Elecraft website.

You may have to replace the firmware (to be determined later), but 
perhaps RF board U7 is not receiving as it should.  If you have a 
'scope, you should be able to see pulses on U7 pins 1, 2, and 3 as you 
rotate the VFO knob.  If all 3 pins show pulses, then most likely U7 is 
not working properly.  U7 pin 7 should move from 5 volts to zero volts 
in CAL FCTR when you tap the BAND+ and BAND- buttons.  If it does, then 
U7 is operating correctly.

Also make a quick check on the Thermistor board - a quick check is to 
measure the voltage at U5 pin 5 - it should be 4 volts or 1/2 the 8 volt 
supply.  If not, check the Thermistor board for solder bridges.  You can 
see the back of the Thermistor board if you remove the Control Board and 
Front Panel.

73,
Don W3FPR



On 10/15/2017 10:02 PM, Mike Maiorana wrote:
> Since fixing my BFO range issue I started going through a full alignment. I
> roughly set the BFO for all the filters. I noticed my frequency display was
> off about 1500 Hz, so I re-set the 4MHz oscillator, then tried to run CAL
> PLL. The CAL PLL started, but never finished. It just sat right around
> 12.1MHz.
> 
> I went back and tried the "PLL Reference Oscillator Range Test", which had
> passed the first time I went through calibration. Now, it is "stuck" on
> 12.097MHz. What is strange is that it will jump briefly when I press Band+
> and Band-, but it settles back to 12.097MHz.