It's a TA81 meaning I think that it will plug into any SDI
device bus which is a pretty common (for DEC) interface.
Interesting from the pictures that it has a diagnostic terminal
port. Makes it more interesting to get if I see one up here again.
The terminal power port may be VT-12 (Termiflex HHT) compatible,
maybe not.
exDEC Field services techs are welcomed to comment further.
John A.