[Elecraft] K2 low battery message

[Don Wilhelm]

Scott,

Your power supply and internal power connections are OK.

Do not be too hasty to believe U3 is faulty.

Did you check the switch or jumper on the top of the control board (just 
to the right of center - next to P5)?  Having the switch or jumper in 
the EXT position rather than the INT would cause exactly the symptoms 
you describe.

If the switch (or jumper) is in the correct position, then if the path 
through the PC traces and resistors Control Board R9 and R10 are 
correct, you should read 2.57 volts on U3 pin 5 (plus or minus a bit).

If you have 2.57 volts on U3 pin 5, then pins 6 and 7 will also be at 
2.57 volts if U3 is working correctly, and you will also have 2.57 volts 
at U6 pin 5.  OTOH, if U3 pin 5 is way off 2.57 volts, then you have a 
problem with either the PC traces or R9 or R10.

73,
Don W3FPR

Scott McDowell wrote:
> Don W3FPR
>
> At the cathode of D-12 in receive mode I get 13.17 volts.
> At the cathode of D-12 in tune mode at 10 watts I get 12.5 volts.
> The K2 display shows .260 ma in receive mode
> and 2.10 amps in transmit ( tune mode).
> I don't get any voltages fromt he display because
> that part doesn't work.
> R9 and R10 both check ok.
> To me, this all seems inline with what you said they should
> be. Am I all wet?
> This leave U3B, so I think I will order another and see
> what happens then.
> Thanks for your help
> 73
> Scott
> N5SM
>
>