Re: Q: Disk drives for //c...

[dalloff@freenet.columbus.oh.us (Dave Althoff)]

Patrick Schaefer (pa.schaefer@fz-juelich.de) wrote:
: Mitchell Spector wrote:

: >     Be aware the DuoDisk is not compatible with the ROM 3 Apple IIgs.

: I remember there was something with two small capacitors on the DuoDisk
: analog board which have to be removed. Perhaps anybody else knows more
: about this?

There are two capacitors which must be clipped from the board on the
DuoDisk regardless of what machine you intend to use them on.  Failure to
do this can cause very nasty failures...for instance, the copy-protection
scheme used on Pascal format applications, and possibly others (when I
watched it happen, it was with PFS:File) can, under certain circumstances,
cause the drive to start writing unexpectedly...say, during a
re-boot...thus trashing the disk without regard to the write-protect switch.

If you plan to use the DuoDisk on a ROM-01 IIgs, there is/are one or two
resistors which must be clipped from the board.  This reduces the drive's
power consumption, and makes it compatible with the IIgs without affecting
its compatability with other machines.

Both of these are described in a technote or two, but I don't recall
exactly which one...I looked it up and modified all three of my DuoDisks,
then promptly forgot about it... 8-)

--Dave Althoff, ][.
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