18 Aug
2005
18 Aug
'05
2:46 p.m.
>>>> "Al" == Al Kossow <aek at
bitsavers.org> writes:
> I think that Al Kossow has lots of experience
reading old
> DECtapes based on the good DecTape archives that he has on
> bitsavers. Al, can you share a little of your experience and
> insight with the rest of us? How well do these things hold up
> 30-35 years later when they are actually being read and written
> to on a TU56?
> --
Al> very, very well.
Al> The tapes have redundant track encoding, they are pretty low
Al> density, and the formulation doesn't stick.
Al> I've read tapes from the mid 60's w/o a problem.
Al> I have a bit-level reader with custom read amps coming to deal
Al> with the couple of marginal tapes and LINCtapes that I have.
Wow.
DECtapes are amazing. They have the oxide embedded between two layers
of mylar, which is why they stand up so well to very heavy use.
It IS possible to wear them out, but not easy. We did it in college,
where we had some DECtapes that were the primary public file storage.
There are stories from DEC about DECtapes that were in someone's
pocket and went through the laundry, without any damage.
paul