We currently have a separate channel for the midstation headset to talk to timing. We would like to have the midstation speak directly into the main timer to starter channel (throught the TdC800). How can we add this in?

Simply jumper the two comm pairs (starter->timing and midstation->timer) together at any point in your wiring and all three spots will have common comm.

James Broder
Broder's Skunkware Scoring & Timing Software
http://www.skunkware.tv

You can also bring the midstation communication down on a seperate pair and plug it into an unused channel. That way the the midstation will only talk to the timekeeper at the 8000. If you jump the start pair like Skunk suggests, everyone will be on the same commo line.