On 09/09/2023 00:02, Fred Cisin via cctalk wrote:
It's odd that he brings up things such as 100tpi drives (VS 96tpi)
and 3" (but not 3.25" on which Dysan bet the company), the very early
40 track 3.5",
--
Grumpy Ol' Fred ci...@xenosoft.com
What confused me, is that i believe the 3.5" Sony Microfloppy originally
had 70 tracks. I'm personally completely oblivious to any 40-track 3.5"
microfloppy formats.
I have a pair of Sony OA-D30V drives, which i believe were the first
commercially available 3.5" microfloppy drives, and they have a single
head. The format the machine that they're linked up to only uses 70
tracks (though the drives might be capable of a few more?) for a SSDD
format of 315KB.
40 track 3.5" microfloppy drives therefore seem more of a branching
derivative rather than the "predecessor" that the article seems to
allude to. Unless, of course, we're talking of an unrelated format that
just used the same size disks...
The early Sony Microfloppy is definitely not quite the standard "modern"
3.5" floppy disk we're aware of today, but is still largely compatible
with modern disks, with slight modification. Namely the drives have no
mechanism of opening the shutters, so i've found the easiest method is
taping the shutters on the disks open with a bit of sellotape.
Josh Rice