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Comment by Tor3

2 months ago

I have a 9-track CCT tape reader/writer which I've used for tapes going back to 1982 or so. I'm kind of surprised that a 1973 tape is 9-track and not 7-track, but then again I'm not certain when the change to 9-track happened. In any case, after cleaning the tape heads with a now illegal fluid all the reading issues I had at first disappeared, and I managed to retrieve the content of every tape I tried, from various minicomputers (some of them DEC).

>then again I'm not certain when the change to 9-track happened

1964, with the IBM 360's 8-bit bytes.

  • So, the 1973 one is likely really 9-track then, possibly 800 bpi. Should be fine reading that one on my drive, if the tape isn't in physically bad shape. Not that I expect them to ship it to me!

"illegal fluid" what would that be? And why illegal? And do you submit the recovered data anywhere, for data archaeological purposes? Seems an important thing.

  • That was a bit tongue-in-cheek.. and a more accurate word would be "banned", not "illegal". It's just something HP used to sell, not dangerous as such, but it's a CFC-based tape head cleaner. Very efficient, and leaves nothing behind. But they stopped selling that particular variant after the Montreal protocol was in place, but I kept a bottle around.

  • CCl4 probably. Carcinogenic, at least for regular occupational exposure.

    • And formerly available at any pharmacy. When I cleaned out my parents house I found a bottle of it in the laundry room. I guess my mom used to use it on stains.