Should I add a "Micro" PDP11/73 to the Herd?

Good Morning, Fellow Classicians... A MicroPDP 11/73 (that's how it's listed) is available on E-Bay, it's not selling, so I can probably get it for the starting bid of five bucks, and it's local. I have no backround with the PDP-11 (and thus my recent query regarding those cards I have). It comes with a TS05 tape drive, which from the photo appears to be a Cipher F880 Microstreamer. I'm thinking of getting it just to have a spare for the Prime's tape drive. Here is what the seller has to say about it: : This is a Digital Equipment Corp Micro PDP11/73 computer : with a TS05 tape drive mounted in a rack. Also included is : what I think is a hard disk unit mounted below the computer. : The front panel of this unit says 'USDC CSS-800 Compact : Storage System'. Also included is a VT320 amber video : terminal. If you look at the photos below you will see that : there is a large space in the middle where something is : missing. I think that there were 2 hard disks mounted in this : space, but they were gone when I got the equipment. I bought : this stuff from the University of Louisville Medical School. : This is one part of a larger system. I have powered the : PDP11/73 up and it seems to boot up OK. When booted, this : is what come up on the screen: Testing in progress - Please : wait 1 2 3 4 5 6 7 8 9 Starting ROM boot 173356 @ I think : the '@' is a command prompt, but I don't know what to do : from there. The CSS-800 unit has lights that come on in the : front, and so does the tape drive, but I have no way to test : them. I can't be sure if this equipment is working properly, so : it is sold AS-IS. : : Should I rescue this machine? What OS do I need to acquire for it? Thanks for all replys, -doug quebbeman