Re: Alignment disk and diagnostic program - ][+ and //e

[Rubywand <rubywand@swbell.net>]

"Michael J. Mahon" writes ...
> 
> It is apparently worth saying again:
> 
> THERE IS NO WAY TO MAKE A USEFUL COPY OF A HARDWARE ALIGNMENT DISKETTE BY USING
> AN APPLE DISK DRIVE.
> 
> The signals written to such a diskette are not digital signals.  No computer
> program can read them usefully.  They must be used by using software to
> position the head (approximately), and then observing the read waveforms with
> an ocilloscope, while adjusting the head positioning stepper.  On most Apple
> 5.25" drives, this can only be done by loosening two screws that mount the head
> positioning stepper.  Re-tightening them without disturbing the motor azimuth
> is somewhat hit-or-miss, and takes practice.
 ....

     This would apply to the kind of disk you mention; but, there are other kinds
of alignment disks and software. For instance, software which does reads while
moving the head up and down from track center can supply a measure of correct
alignment; and, the disk would be copiable.



Rubywand