What interface should I be looking for to hook it to
the UNIBUS ?
Some variation of an unformatted tape drive interface. They are slight
variations between vendors, so you need the right edge connector to idc
interface card at the drive. There should be some indication of who made
the interface card on the PC board.
The three connectors are read, write, and control.
Unibus controllers often are either a system unit or a single quad board
with a second board for 1600 BPI PE support.
The Emulex TC11 and Western Peripherals TC-131 manuals are up on
bitsavers
Plessey and Dilog made similar controllers.