[Elecraft] Adding a (second) straight key jack to the K1?

[Mike]

Dave Ek wrote:

> I was really thinking of was *bypassing* the controller with the second
> straight-key jack, accessing the keying circuit directly. Generally, all it
> takes is to ground the right line in order to key the rig. So I guess my
> real question is "is there easy access to the keying circuit?"

Dave,

I may be wrong, but my understanding of the K1 circuit is that the
transmit or receive mode is set by *two* outputs from the main MPU (6T
and 6R/AUX).  I think 6R/AUX is also the one-bit aux bus communication
line through which the various other PICs in the K1 communicate with the
main MPU.  The Elecraft folks could best supply a definitive answer, but
I think there are thus two MPU output lines which have to change state
in some coordinated fashion to key the K1, and the only place control of
these two lines tie together is through the MPU.  There may also be the
problem of conflicts with the multiple uses associated with the 6R/AUX
line if you try to key it directly.

If you don't have your K1 yet, you might look at the schematics on the
downloadable manual at the Elecraft site, and see if you reach a
different conclusion.

73,
Mike / KK5F