"Mike Luther" bravely wrote to "All" (11 Mar 04  14:43:08)
 --- on the heady topic of "Reading H/Zenith 729K disks"

 ML> Does anyone here have a copy of a utility that will run in MS-DOS or
 ML> in a DOS-VDM in OS/2 which will read the older Heath MS-DOS 5-1/4"
 ML> floppy disks that were formatted to 729K?  That's the ones which were
 ML> actually 360K with the factory supplied hole re-inforcement.  Heath
 ML> embarked on a massive program to double density format and write these
 ML> disks in the 1.2MB 5-1/4" floppy disk drives way back when.  I used
 ML> this format with Z-120's for years.
 ML> If you have two of the drives or a hard disk and one ..  you can copy
 ML> them to the later 5-1/4" 1.2 MB density flopppy disks or the later yet
 ML> 3-1/2" 1.44/2.88 MB floppies.  I have a large stack of these I want to
 ML> move to 3-1/2" diskettes or archives.
 ML> I used to have a copy of UNIFORM which is a DOS device driver that you
 ML> could over-install in CONFIG.SYS in MS-DOS which I think would do
 ML> this.  Someone else in the UseNet forum has suggested another
 ML> executable that would run under DOS to do this.

 ML> Anyone here have a copy of such a utility?

Not here I think but, if one knew the Zenith disk structure, perhaps
it might be possible to tweak the MS-DOS drive table parameters and
then do a sector dump to file using debug or a BIOS service. The
result would be a data image of the disk. Then later it would simply
take reading the directory table info to recover the sectors into
their respective individual files. BUT it's only doable if the sectors
can be dumped from DOS.

The TRS-80 had a similar utility that allowed reading its disks from
MS-DOS though there were some limitations. BTW there was even an
emulator which allowed running CP/M using a V20 cpu in 8080 (Z80?)
mode on an XT. Perhaps there exists an emulator for Zenith machines
too?

 Mike
 ****

... "If it ain't broke, you're not tryin!" - Red Green
--- Blue Wave/DOS v2.30