Re: versioned filesystems in linux (was Re: kernel support for

Richard B. Johnson (root@chaos.analogic.com)
Fri, 25 Apr 2003 14:34:04 -0400 (EDT)


On Fri, 25 Apr 2003, John Bradford wrote:

> > > Just wondering how difficult it would be to make a 9-track tape drive
> > > from scratch, and connect it up to the parallel port... Do you think
> > > that old hard disk motors, from 5.25" MFM disks be powerful enough for
> > > the 120IPS tape transport?
> >
> > The disk-drive motors, even for the 5.25 floppies were pancake motors
> > designed to directly turn the floppy, or run a belt with a small
> > ratio. You need a motor that runs at relatively high speed to turn the
> > capstan. If the capstan was 1 inch in circumference (about 0.2'' in
> > diameter), you need 120 revs/sec = 7200 r.p.m. You won't do this with
> > a floppy motor.
>
> I was thinking of hard disk motors... Actually, some of those would
> be 3600 r.p.m., so if we used a large capstan, we might be in with a
> chance :-). (You'd really need to drive the actual reels as well,
> though, I can't see us starting and stopping the whole thing very
> quickly just using the capstan motor.)
>
> John.
>

Oh the hard-disk motor that drive the RA80 will rotate the
building if it ever stalled. I understand that the mechanical
designers for that make vacuum cleaners right out of college.

Cheers,
Dick Johnson
Penguin : Linux version 2.4.20 on an i686 machine (797.90 BogoMips).
Why is the government concerned about the lunatic fringe? Think about it.

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