Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!sun-barr!sun!imagen!atari!apratt
From: apratt@atari.UUCP (Allan Pratt)
Newsgroups: comp.sys.atari.st
Subject: Re: HELP! (Damaged data)
Keywords: floppy disk, damaged data
Message-ID: <1502@atari.UUCP>
Date: 18 May 89 17:46:36 GMT
References: <3475@ihlpm.ATT.COM>
Reply-To: apratt@atari.UUCP (Allan Pratt)
Organization: Atari (US) Corporation, Sunnyvale, California
Lines: 28

In article <3475@ihlpm.ATT.COM> jshwang@ihlpm.ATT.COM (Hwang) writes:
> I have an atari 1040st. Sometimes when I try to run a program,
> the disk drive (built in the st) makes a sick sound (I don't
> know how else to describe it..it is not the normal rrrrrrr,
> but r..r..r..r), then a banner comes up saying the data on
> the disk may be damaged. The program will not run.

What's happening when it goes r..r..r..r is that it's trying to read a
certain sector, failing (after five revolutions), and the software
"reloads the head" -- that is, it seeks track zero, then seeks back to
the track where the data is supposed to be.  It does this three or four
times. 

This can happen if the disk is damaged, if the floppy's heads are dirty
or damaged, and, most especially, if the floppy's heads have come out of
alignment with the "ideal" for 3.5" drives.  Take the machine to your
dealer; s/he can open the drive, clean the heads (don't use a "head
cleaner" disk; use the kind of kit that comes with Q-tip-style
applicators), and realign the drive if necessary. 

There's a gotcha to realigning your heads: if you've been writing data
to disks with misaligned heads, then you fix the heads so they're in the
"standard" alignment, you might not be able to read your own disks any
more! This is usually not a problem, but something to watch out for. 

============================================
Opinions expressed above do not necessarily	-- Allan Pratt, Atari Corp.
reflect those of Atari Corp. or anyone else.	  ...ames!atari!apratt