Will, no idea on the data front. Did TurboDOS have built in multi-user support (I know nothing about it)? If not then I'd definitely think that the version on this machine was custom, as it has support for at least 4 if not 5 terminals in its current state. That's just going by the cables at the back; there's a lot of unused pins on the card edge connectors, so given that the website claims support for 62 terminals I expect it could make use of some breakout box arrangment to give more 25-pin terminal connectors. unfortunately I hit a bit of a snag with my machine. Following the flood damage the previous owner had tried to fix the system. Trouble was, the machine has two backplanes to it - the upper one with one row of card sockets and the lower one with two rows. System cards from the top rack will also plug into the bottom rack (which contains the PSU, mains voltage, and a spare slot for some unknown board). The disk controller had been plugged into that spare slot... :-( It wouldn't have got any mains voltages but it would have got +5 and +12V on all sorts of pins that it shouldn't have. I also found that the disk data bus (SCSI? SASI?) terminators had been misaligned and so it's possible some of the data lines were shorted together or at least had a low resistance connected across them. Curiously, the disk controller and the board the converts the system's SCSI/SASI bus to MFM look to be identical on the P3500 (from the photos on the website that Fritz posted about). So if one of those ever shows up, at the very least it'd be invaluable for checking that the hard drive on this 3800 is still operational - and in the absence of schematics for the 3800 it'd probably be very useful for fixing the 3800's disk controller. I'm not sure - I did a quick hunt on the web and there was very little information around. One site seemed to imply that it was much older technology than the 3800, but another site gave the impression it was much newer. Uless the model number was reused they can't both be right :) cheers Jules __________________________________________________ Do You Yahoo!? Everything you'll ever need on one web page http://uk.my.yahoo.com