[Elecraft] "Hung" Auxbus?

[William M. Spaulding, Sr.]

Dear Elecrafters,

A while ago after making some A to B mods, I turned on the K2 to the blast
of white smoke from the lower from corner.  From all I could tell initially,
the only thing I could find wrong was that the inline fuse from my supply
had blown (5 amp fuse).  When I applied power the second time, nothing
happened.  Using the front panel and control board from another K2, all
turned on, but it acts as if there is a key being held down.  But it has
nothing to do with the keyboard and controller.  Something on the RF board
is making the MCU believe that a key id pressed and is waiting for it to be
released.  When you turn the radio on, it shows the software revision just
as if a key was being held down.  But the source of the problem is on the RF
board.  I have removed all options and replaced jumpers.

Anyone got a clue.  I tried swapping a known good RF board I/O controller.
Any clues.  I am a long ways from an AuxBus "driver"! ;-))

Thanks for any help,

Bill
NA7Y