Brendon - Evan gave you a pretty good rundown of your questions.? The extra cable is for, I think, plugging in to the board and remote mounting some of the controls and jacks.? Referring to the schematic it looks like they provide off-board support for volume, mic, and speaker.
Have fun!? I now have three of these little gems and they are great!
73,
Justin B.
KI5GKD
