[Elecraft] K2 keyer autodetect mode

[Chris Kantarjiev]

I've always thought this was pretty neat - I could pull out the
paddles and plug in the (suitably wired) straight key and not have
to mess with the menu settings. It occurred to me that I could
even have both plugged in at the same time and go back and forth
(though my desk space doesn't really provide for this).

When I started exploring computer keying, it was clear that I needed
something to allow me to have both the computer cable and paddles
plugged in at the same time. Gee, while I was at it, wouldn't it
be nice to be able to leave computer, bug, straight key *and*
paddles plugged in at once?

Sure. That would be easy; the K2 manual basically gives the required
hits. But making it small was the problem (see above comments
about desk space).

After several trial orders of parts, I discovered that you can make
it pretty darn small. Four Switchcraft 35RAPC2BH3 horizontal mini
stereo jacks can be crammed into a Serpac C-4 enclosure. Just.  The
terminal spacings aren't quite right for .100" perfboard, so I wired
it up ugly style, using magnet wire for the "bus" connections. Two
diodes, a few 1/4" holes, a 6" stereo extension cord pigtail and a
grommet and ... just what I wanted!

Thought I'd pass this along, mostly to get the part numbers
into the archives. 

73 de chris K6DBG