Marty Greene, There are others of us who have TI 990/systems in storage. I have 2 990/10 systems. DX-10 OS with 10M cartridge (CDC?)drives. Mine came from a Paradyne Corp Modem Analysis system tracking 300 Paradyne 2400 Baud multi-drop circuits on an 800 hz subcarrier over dedicated lines. So I have lots of serial ports...Each modem had data and an analysis port. Sincerely Larry Truthan I may also have a Xerox Sigma diagnostics tape and or journal somewhere in the basement.