197. Disc hint
     ~~~~~~~~~
If you are using discs that have previously been formatted on a 40-Track
drive, you can sometimes have problems using them on an 80-track drive.
Theoretically, this shouldn't happen, but apparently it does. The cure is to
'wipe' the disc using a bulk eraser electromagnet, or a powerful permanent
magnet, and then reformat it.

This same technique is also useful when saving files onto 40T discs using a
40/80 switchable drive set to 40. If the disc has previously been formatted
and used on a true 40T drive, wipe the disc with a magnet first and reformat
it as 40T on the switchable drive. The files should be copied off this disc
as soon as possible, and then the discs reformatted on a true 40T drive.