[Elecraft] K3 appears to be bricked

[Mike Murray]

I was in the process of updating my K3's firmware this morning when
something apparently burped leaving the K3 bricked.  The radio is wired
directly to a power supply  which also feeds a RigRunner for other stuff.
At the time I was also using a small 12V air compressor on the RigRunner.
I don't think it was involved, but can't say for sure.

The TX light is flashing, the display shows "MCU LD" and power button won't
power it down.  I've tried forcing a firmware download several times,
explicitly following the instructions in the K3 manual without success.
The K3 Utility program can't find the rig on the prior COM port being used,
nor on any other available COM port, so I suspect that's a major clue.
True COM ports are not available on the PC so I'm using a StarTech 4 port
USB converter that utilizes the FTDI chips.

Anyone have any ideas I can try???

Mike - W0AG