[Elecraft] Dead K2 - Could it be the MCU??

[Tom Mc]

Hi all,

  I posted the e-mail below to the list, earlier today and one of the guys
on the list said it sounded like it could be the MCU.

I wonder if anyone has any thoughts on this.  I upgraded the MCU ti V 2.02
when I purchased the KI02 module, a few months ago.

I looked at the MCU and I am getting 5 volts on the pins I should be.  I
still have the older MCU that I took out when I got the new one.  Do you
think I should try swapping it back in?  I afraid I may damage though.

Thanks
Tom
WB2QDG
K2 S/N 1103
-------------------
Here is the earlier post:


Hi gang and thanks for any help you may be able to provide,

  My K2 was working fine (I have the Internal Battery, ATU, Noise Blanker,
KI02 and 2.? firmware installed) and then yesterday I noticed some erratic
readings on the display from the internal voltmeter.  On transmit it was
jumping around from about 8 volts to 20 or 25 volts (well that was the
reading).  I thought perhaps I needed to charge the battery, so I did.
After a while the same readings were showing.  I then disconnected the
battery and worked only from the external Power Supply.  Still the same
erratic readings.  So I started taking voltage readings at various points
inside the rig with my DMM.

Then, without fanfare, the rig went dead.  I thought I tripped the fuse, but
that wasn't the case.

I am getting the PS voltage through the RF board to the Plug to the Control
board (Pin 1 of the plug is reading full PS voltage).  I am also getting the
appropriate voltages into and out of the 8 and 5 volt voltage regulators.
But the display is not lighting up and the relays aren't switching when I
turn the rig on.

That's as far as I went as I didn't know where to check next.


So if anyoneone can tell me were to trace the voltages next, or has any
other ideas, I wold be very appreciated.

I've had the K2 built for about 18 months now and this happened, out of the
blue.

Well thanks for your help

Tom
WB2QDG
K2 s/n 1103

PS Can we postpone FD until I fix this???