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KellyCriterion

720 kb SD or 1.44 MB DD ?

:-D

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Sorry, nitpick: 720kB DD 1.44MB HD

++1

:))

It's funny that we've always called them "1.44 MB" disks when they actually hold 1440 KiB, which is 1.41 MiB or 1.47 MB.

"1.44" is a horrible mix of binary kilo and decimal mega which makes no sense.

With the GNU Units program, I have this defined in my ~/.units: "floppyMB 1000 KiB"

Is it useful? Perhaps not, but you can use it to translate "1.2 floppyMB", "1.44 floppyMB" into other units.

Probably because they have 2880 sectors.

One could cheat and run a SuperDisk drive, with 120 MB! Though that's not in the spirit of the game.

but do you remember ZIP-drives? :-) (was that the name?)

Yes. Along with the feared click of death.

Yes! Superfloppy!

Iomega's awesome Zip drive disk (100MB, 250MB, 750MB capacities) , I think I still have a 250MB zip drive somewhere in my home attic.

They required a dedicated zip drive (took up same sized slot/bay as a floppy disk drive), but (if I recall right) that drive was backward compatible standard 3&1⁄2-inch 1.44MB floppy disks.

Interestingly, these drive also came in variants to work with different types of interfaces: IDE, ATAPI, USB, SCSI, FireWire.

Zip drives filled the portable storage niche, until CDs and DVDs replaced their need.

https://en.wikipedia.org/wiki/Zip_drive

I found it cool that floppies and superfloppies had label stickers on which we can write (with a sketch pen) to remind the user of what content the disk is intended for.

There were some nice cameras that used Zip disks for storage! Very convenient for photographers working on multiple projects or sessions.

https://www.digitalkameramuseum.de/en/prototypes-rarities/it...

> They required a dedicated zip drive (took up same sized slot/bay as a floppy disk drive), but (if I recall right) that drive was backward compatible standard 3&1⁄2-inch 1.44MB floppy disks.

Zip was a completely unique physical format, and had no backwards compatibility with standard 3½" disks.

SuperDisk, on the other hand (in both the LS-120 and LS-240 variants) was backwards compatible with standard floppy disks in the same drive.

ZIP Drives died as Minidisc died: MD was a very proper medium, but the inventors made some wrong decissions

I have a bunch of them, some SCSI ones in old samplers.

Hey, my oscilloscope has one of those!

720k? In my day floppy disks had 96K and we liked it!

I liked when floppy disks were actually floppy.

3.5" floppies are still floppy. The case may be hard, but the floppy flops.

this was 8.25" back then?

RX-01 DEC / IBM 3740 compatible was 77 tracks, single-sided, 128 bytes per sector and 26 sectors per track. Total 256,256 bytes. FM Modulation. 360 RPM. Disk to drive buffer: 4 µsec per data bit. Track-to-Track Seek: 6 ms. Head Settle Time: 25 ms. Average Access: Approximately 262 ms. 8" diameter diskette

One of these was used to load the microcode into the VAX-11/780 upon boot.

My old PDP11/73 (now in a museum) had two RX02, never had an RX01. Surprisingly fast! It also had two RL02s and a couple of RD54s in.

Building an RT11 system disk onto an RL02 off another RL02 made the downstairs neighbours complain quite a lot, even though the floor slab in my flat was about 40cm thick concrete. They didn't muck about with these 1960s tower blocks but it was no match for a pair of pint glass sized head actuators and a pair of washing machine motors.

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