High pitched squeal/whine/warble

[Bob Wilber]

}I bought my 3B1 (2M/40M 3.51) 3rd hand about 3 months ago.  When I first got
}it, it would whine occasionally, with about a 2 minute quiet period in
}between whines.  It has now progressed to the point where it is whining/
}warbling constantly.  It is hard to localize the source of the sound,
}but I'm afraid it's the disk, since I can hear the fan running quietly
}in the back.
}...
}Peter H. Schmidt

This is a common problem, caused by the anti-static tab in the disk getting
worn by the rotating spindle.

To fix:

Open up your 3b1 (the hard part :-( ), take out the disk drive, and remove the
PC board at the bottom of the disk drive.  (Be sure to note how the connectors
go so you'll be able to reassemble it properly.)  On the other side of the PC
board you will see the copper anti-static tab.  Bend it down, away from the
disk spindle, and reassemble.

No harm seems to come from having the anti-static tab not quite touch the
spindle.

Needless to say, back up the disk first.

Bob Wilber      wilber at research.att.com