Many thanks to the Listmembers who have offered suggestions and assistance and info.. I have discovered (and rectified) the problem with my RK05 talking to it's host. I could get into a long shaggy-dog story here, but basically I had the *drive* end of the interface cable in bass-ackward. (Lame excuse: it's the end you can't see) And now the terminal sez: RT-11SJ V02C-02 . kewl, huh? And, even though the problem turned out to be a forehead-slapper, I must say that I have learned great gobs of stuff about how the drive works, how it interfaces, and what makes it tick. I would *never* have had the opportunity to get such (rare) understanding, had it not been for the long diagnostic journey. And that is one of my goals in collecting these things: to know them well enough to keep them on the air, and to be able to share that knowledge with others in return. Thanks to Tony Duell, Tim Shoppa, Ward Griffiths, and Huw Davies for their generous assistance. Now: get the RL02s on-line, find formatter for the Kennedy 9trk, find an interface for the System Industries 470M drive, get Unix running, &tc; &tc; &tc. But.. TRW Ham/Electronic/Computer swapmeet is tomorrow, the 28th (Sat) here in SoCal... and I'm heading that way... to find all the goodies before Marvin has a chance at them. ;} Cheers John