hi bob,

Funny you should raise this as I was looking for this info last week and couldn't find it either.
[maybe Morphic Resonance?]

I do recall a post from Hugo about what each wire "does" on the tuner connector, but he did not elaborate on which tuner connector pin does what in detail.

Note I am sure that there are 2 inverted TTL serial link signal wires between the Tuner and the Empeg - 1 for data from the Empeg to the Tuner, and another for the data from the Tuner to the Empeg.

You should also note Hugos comments about needing 10K in-line resistors between the empeg and the "serial" device (if the other deivce is not an actual Tuner module) to prevent lockups and other problems during docking/undocking.

I also point out Hugos comment that Mk2A's have these resistors on the main board already, so do not need them, its only the original Mk2's that need them.