[Elecraft] K2 [DISPLAY] Button

[Don Wilhelm]

Ron,

Do you have the Control Board P7 jumpered between pins 2 and 3 (marked INT)?
If so, what is the voltage at P7 pin 3?  How about pin 2? - both should 
be about 0.3 volts below your supply voltage.  What is your supply 
voltage when the K2 is powered on?  (Measure at the anode of RF Board 
D10).  What is the voltage at the cathode of D13?
What is the voltage at each end of R9 - one end should be the same as 
the cathode of D13 and the other end should be very close to 20% of the 
voltage at the cathode of D13.  Control Board U3 pins 5, 6, and 7 should 
also have the same voltage.
If any of these measurements are incorrect, look for the soldering 
problem - connection not adequately soldered or a solder bridge.  Also 
check to be certain R9 and R10 are the correct values.

73,
Don W3FPR

Ron McCurdy wrote:
> I'm building a K2.  The [DISPLAY] button shows a voltage of less than 2
> volts and it is erratic and, the current is shown as 0.00.  I have checked
> the voltages at U3 and they are 2.633 at pin 5, 6, & 7, and 13.75 at pins 2
> & 3.  Pin 1 is .571.  I measured the voltage at Vsense on the MCU pin 5 and
> it was 2.669.  Where could I be losing the signal to the lcd??
>
>   
>