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Hi John, Based on my hazy memories of the 80's. I have certainly not handled a 1/2" open reel tape in this century. The MSU Perm. Tape ID doesn't necessarily mean it was create at the MSU CL. It just means that it was stored there. If you needed the information on that tape you would put a request in in your job control to have that tape mounted, and assigned a unit number(?) before your program ran to read or write that tape. I would think that 6250 BPI is pretty much anyone that can recover a tape needs to know. At some level these things are pretty standard. I think they are 9 track with normally 8 tracks being data and the 9th being parity. Assuming this is some text based data I guess there is a 50/50 chance of the data being ASCII or EBCDIC. Of course if the data is binary all bets are off. I spent my first job at MSU writing programs to unpack satellite data. I remember one data set had 10-bit bytes so it was packed on the tape as 3 10-bit bytes per 4 8-bit bytes on the tape. Of course tapes were never suppose to be stored for more than a few years without be "exercised" -- basically run through a tape drive and then rewound back to the original reel. The point of this was that the data from the tape would have a tendency to bleed to/from the layer of tape above/below it. When you took it off the reel and put it back on again you were betting that the tape would be shifted a little bit so that exact same bytes were not on top of each other to reduce the effect of the bleeding. Don't know if this was really a problem or not, but would worry about a tape that has sat in a drawer for ~30 years. Anyhow my $0.05 worth. Brian On 3/26/13 10:40 AM, John Gorentz wrote: > Youngsters under age 50 can ignore this message. It's only for old-timers. > > If an old tape reel from the 1980s has a label on it that reads, > "Memorex Cubic 6250 BPI SuperReel" and a typed tag saying "MSU > Permanent Tap ID Number B 577" does that mean it was created at the > Computer Lab, as it was then called? > > A former faculty member is interested in having a data recovery > company try to recover files from it. I've run the possibility past > the folks at werecoverdata.com (which I used a couple of years ago to > recover data from a crashed disk) and they didn't outright laugh at me > . But we need to supply information about the tape. Maybe 6250bpi > will suffice, but maybe other information about the system that would > have been used to write the data would be useful. Does anyone > remember the systems that would have been used to write such tapes? > > When the faculty member brought this up, I first thought she was > talking about a tape that I remember writing for her when she moved to > Australia back in the mid 80s. But I think our tape drive was a 1600 > bpi thing. I can't remember the model of the tape drive, but it was > purchased with an early VAX-11/780 computer. Googling has led me to > mentions of a model TU81, which is a model name I sort-of recognize, > but ours might have been older than that. But it probably doesn't > matter, because now this doesn't look like one of ours. I haven't seen > the tape at first hand. It's still in Australia or some such place. > > Any information would be appreciated, including any stories you know > about recovering data from tapes that old. > > John Gorentz