[Info-vax] DLT Tape degaussing services

[Rich Jordan]

On Mar 19, 9:32 pm, "Richard B. Gilbert" <rgilber... at comcast.net>
wrote:
> Rich Jordan wrote:
> > On Mar 19, 2:02 pm, "John Smith \(not the one @ HP\)"
> > <a... at nonymous.com> wrote:
> >> "David Mathog" <mat... at caltech.edu> wrote in message
>
> >>news:gpopc4$8gi$1 at naig.caltech.edu...
>
> >>>> I'm certainly
> >>>> willing to try a smaller unit (missed one on ebay yesterday that was
> >>>> for reel to reel audio tapes) but expect it won't be overly
> >>>> effective.  So far no luck at locating a nearby service.
> >>> See what's available at the local Universities and research labs.  NMR
> >>> machines and cyclotrons have enormous magnets.  How far are you from Fermi
> >>> lab?
> >>> Regards,
> >>> David Mathog
> >> How about the nearest Navy Yard when they degauss their ships? Put the tapes
> >> in plastic bags and hang them over the side as the ship is degaussed. Ought
> >> to work.
>
> > Heh.  Unfortunately I doubt the Navy does anything like that here in
> > Ill Annoy.  I actually did look around to see if there was a wrecking
> > yard that used a crane with an electromagnet but couldn't find one
> > (and if I did I doubt they'd be willing, but who knows).
>
> > I knew someone at Fermi but he left.  Without that contact I'd hate to
> > bother them for something like this.  Fun thought though...
>
> > Maybe I should build a railgun... if it didn't erase them it could
> > launch them pretty hard; more fun than a sledgehammer for data
> > destruction.
>
> > I did some more digging and there seems to be a breakpoint at about
> > 3500-3700 Gauss where the sellers start claiming the ability to erase
> > DLT cartridges (and around 4350 Gauss for SDLT-2 and higher.  I read
> > reports that the Radio Shack high power unit was not able to do the
> > job on DLTTape IV 20GB cartridges (ironically the same situation;
> > someone trying to make tapes used on a real DLT drive usable on a
> > VS80).
>
> > Found one service that may end up costing about $4.00/cartridge by the
> > time shipping there and back is considered, and nothing local so far.
> > I can get new tapes on Ebay for very close to that price... I think
> > we're going to end up doing the crush kill destroy thing on the
> > tapes.  A shame, but its not worth the time and effort to get them
> > wiped.
>
> > Rich
>
> Is there some reason you can't simply INIT the tapes and reuse them?

Yep.  They were used on a DLT8000 drive.  The potential target has a
VS80 drive, which uses a different means of recording (apparently).
The VS80 will not allow a tape that has been used on a DLT8000 to even
remain loaded; it ejects it unconditionally.  No possibility of
performing an INIT.  A brand new tape, or one that has been properly
degaussed/erased, can be used in either drive according to the manual,
but once a tape is used in a DLT8000 it becomes unusable in a VS80.

Its strictly an economy thing for us.  The tapes, which are nearly
new, need to be retasked or destroyed.  Retasking outside of our
office would require erasing (and we don't have a compatible drive to
re-use them as-is) in any case.  Erasing would coincidentally make
them usable at the VS80 customer site who desperately needs more tapes
but doesn't have the budget for it right now (and we'd be heroes ;).

If we can't erase them they get sledgehammered.

Rich