dlarson@blake.u.washington.edu (Dale Larson) (09/30/90)
I just finished going through a bunch of disks full of obsolete stuff and re-formatting a dozen of them. 4 failed (a sony, a maxell and two of whatever WP releases upgrades on). I tried formatting most of the failures again, none would. I've also had a couple of disks fail while using them (though only for back up) and those disks had been reformatted. I am using my A3000. Question: Is there any reason that reformatting these disks might cause problems? Question: Isn't this a ridiculously high error rate? Question: Could my df0: be borderline in need of repair? Question (long shot): Could there possibly be anything about my A3000 or 2.0 which would cause a higher error rate without my machine being in trouble? -- -Dale Larson (dlarson@blake.u.washington.edu)
aduncan@rhea.trl.oz (Allan Duncan) (10/03/90)
From article <8335@milton.u.washington.edu>, by dlarson@blake.u.washington.edu (Dale Larson): > > I just finished going through a bunch of disks full of obsolete stuff and > re-formatting a dozen of them. 4 failed (a sony, a maxell and two of > whatever WP releases upgrades on). I tried formatting most of the failures > again, none would. I've also had a couple of disks fail while using them > (though only for back up) and those disks had been reformatted. I am > using my A3000. > > Question: Is there any reason that reformatting these disks might cause > problems? > > Question: Isn't this a ridiculously high error rate? > > Question: Could my df0: be borderline in need of repair? First some fundamentals of magnetics - when you record, you apply a field, then remove it, leaving a residual field in the magnetic media. If you wish to change that residual field, it is necessary to apply approaching the same level of field that was originally used. The field that a disk drive produces can be reduced by dirt or wear/alignment error, and has a degree of tolerance at manufature. I have fond that about half the permanent errors on my 1000 df0: can be overcome on another drive, whereupon the disk is reusable. Better would be a bulk eraser. Shop around the drives you have access to and see if you can recover the disks - it is a fine line between being able to overcome the old hard spot, and creating new ones with a high field head! A word of warning - keep clear of Preformatted floppies - you may not be able to reformat them to AmigaDos for the above reasons. Blank (bulk erased) are safest. Allan Duncan ACSnet a.duncan@trl.oz (03) 541 6708 ARPA a.duncan%trl.oz.au@uunet.uu.net UUCP {uunet,hplabs,ukc}!munnari!trl.oz!a.duncan Telecom Research Labs, PO Box 249, Clayton, Victoria, 3168, Australia.