3.5" DSDD disks mostly bad

[Dave Dunfield]

> > How does an entire lot go bad?  Are you seeing an exorbitant amount of
> > bad sectors after a format?
> 
> The most handy machine for testing these is a Linux box.  Since these were
> previously used on an Amiga, I need to do a low-level format before using
> mformat.  Here's the typical response:
> 
> # fdformat /dev/fd0u720
> Double-sided, 80 tracks, 9 sec/track. Total capacity 720 kB.
> Formatting ... done
> Verifying ... Problem reading cylinder 62, expected 9216, read 2048
> 
> These disks were found in a box, not protected very well from dust.  That
> might have done it.

Is the drive (heads) clean? Try giving the drive a good cleaning before you
chuck the disks.

Dave

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dave06a (at)    Dave Dunfield
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