[Elecraft] Re: K3 QSY using mic jack

[Dave G4AON]

I've just checked my Kenwood MC-43S which I use with my K3 - the "UP" 
and "DWN" buttons ground pins 3 and 4 when pressed.

73 Dave, G4AON
K3/100 #80
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I'd like to build a little QSY switch box that will sit on the table next to
my keyboard. My question is: exactly what do pins 3 and 4 of the mic jack
need to "see" in order to perform their function? I think it is more than
just a simple closure to ground, but I'm not finding the info anywhere. Can
anyone help?

Thanks,
Tony / KM0O