Adjusting speed of a Disk II?

[buck@wam.umd.edu (Bryan Roger Buck)]

I took my venerable Apple II out of cold storage recently, and discovered that
one of my drives (a Disk II -- you know, the old full-height 5.25" ones?  I
said it was venerable. :) is seriously off-speed.  I have a program that can
tell me how fast it's running, but what I don't know is where the control is
in the drive that I have to tweak.  I know there's a speed-adjustment screw
in there somewhere, but I can't find it.  Can someone tell me what to do?

Thanks,
Chris Nebel

[If you respond by mail, please mail to "nebel@systemix.com" -- I'm posting
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