[Elecraft] K3: Unable to update firmware by RS-232 port

[Joe Malloy]

Hi, all, hope someone can help!  I have updated my K3 with just about 
all firmware that has come along since I put the rig together in March, 
2008 (ser no 584) and never had trouble -- until now.  The K3 Utility 
suddenly reported that no K3 communications are available.  I've done 
some of the updates (the RXA board, CW Rise time, KIO3 Remote Module, 
LINE OUT and Speaker amplifier) and have had the rig on the workbench a 
few time looking for an obvious error I have made.  To date, the error 
remains elusive.

Anyone have an idea of what I should look for?  TIA!

73,

Joe, W2RBA
w2rba(at)arrl(dot)net