[cctalk] Re: For Fred, especially: "Everything I know about floppy disks"

On 09/09/2023 00:02, Fred Cisin via cctalk wrote: 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