Hello
Does anyone know were the PBX connects to the Telecenter 21 goes on the main ckt. board.
Jim

You can punch down to a spare Master Phone or Classroom Station port. You may need the programming software to grant the particular port access to do what you want (e.g. page, intercom, etc...)
At the punch block, master ports from top to bottom are tip, ring, data+, data-. Punch to tip and ring. Station ports from top to bottom are speaker, speaker, tip, ring. But tip and ring are only active for phone use if the port is programmed to have a phone connected there.

Thanks Tim i found the cable the school just cut over to VOIP.
Jim