Hi The Tektronix 4970 does something similar to an IBM 3174 or 3708. It hooks up terminals to an IBM mainframe, in this case Tektronix graphics terminals, see [1], p.36ff. Is anybody here in possession of the software that runs on it? -Alex [1] http://bitsavers.org/pdf/tektronix/tekniques/vol7/Tekniques_Vol_7_No_03.pdf