[Elecraft] K2/100 RS-232 problem

[Michael Pfeuffer]

Hi all,

I've got a K2/100 that was damaged a while back in a close lightning 
strike.  Sparky came in via the phone lines, traversed my modem & into a 
multi-port RS-232 controller.  It took out several RS-232 devices, 
including the serial port on the K2.  All other K2 functions have been 
working fine since then.

I am getting data out of the K2, but it is not responding to commands 
from the PC.  I found that that U4 ( the MAX1406 ) on the KPA100 board 
was bad, and replaced it.  I was then seeing data on the RXD pin of the 
MCU, but it still wouldn't respond to PC commands.  I have now replaced 
the MCU, assuming that the RXD input was bad.  Alas, still no joy.

I've been pouring over control board schematic, but am not sure where to 
proceed.  Any suggestions?

Thanks,
--Mike  WQ5C