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Ask HN: 3.5 inch diskette read errors, would a period correct drive do better?

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Re: Ask HN: 3.5 inch diskette read errors, would a period correct drive do better?

#13
If you have something that's not already archived on archive.org, you might consider reaching out to Archive Team, who may be able to help you figure out the best way to read it accurately and avoid any errors.

(If you have something that is already archived on archive.org, the best way to get an accurate image of it would be to download it from there.)

https://archive.org/details/msdos_Super_Solvers_Spellbound_1...

Re: Ask HN: 3.5 inch diskette read errors, would a period correct drive do better?

#14
post #3

10 years ago I heard “you’d better read all the floppy disks you’ve got now because you won’t be able to do it later.” You might do better with better hardware, you might not. This thing can get at the raw data https://en.wikipedia.org/wiki/KryoFlux which might let you get most of the bits from a bad block. See https://goughlui.com/2013/04/21/project-kryoflux-part-1-the-...

Neat! Thank you for the info on that one. Bookmarked! Before I spend well over $100 importing that device, I previously was thinking of brining up a 2001 era motherboard with a USB stack and can natively host the drives, but the 486 that has sat unused may be a solid option. I presumably can find a way to transfer data to a modern system over serial cable or something.

Almost any two floppy drives you can get a hold of will be mechanically different in sometimes significant ways.

I've got one business tower from over 20 years ago still having the floppy drive connected directly to the motherboard the traditional way.

Plus 3 USB models from HP, Sony, and Teac and they don't all behave the same.

Last month for another floppy article I mentioned that one pack of old floppy disks are offgassing(!), the way they continue to inflate the ziplock bag they are in. Replaced the bag with an new Ikea "ISTAD" ziplock and it's almost fully inflated again by now.

Re: Ask HN: 3.5 inch diskette read errors, would a period correct drive do better?

#15
post #12

FWIW, it turns out that all USB floppy drives nowadays are made in the same factory, and all of them are kinda glitchy. Go buy an older model on eBay instead of buying new.

Interesting. Can you tell me more about this? I have an upcoming project that will use these disks. Thanks!

Re: Ask HN: 3.5 inch diskette read errors, would a period correct drive do better?

#17
The disk appears visually in good shape. It has been stored all these years in the original box in an air conditioned basement. I am not seeing any white material or other obvious corrosion. However, I can confirm that my first attempt to read the imaged data failed. I did not record the output from ddrescue but it was something like 34% on the 1.4 MB. Got a corrupted screen when trying to run the installer in a Windows 98 SE QEMU vm. I have not dug into it very deeply.

Re: Ask HN: 3.5 inch diskette read errors, would a period correct drive do better?

#18
I have other disks, including personal files, that are not mass market. Including some very fun early "Rietta Solutions" programs by my learning days. I was very early mimicking the look and feel of commercial shareware at the time, including printing diskette labels with version numbers and copyright dates with an inkjet.

Re: Ask HN: 3.5 inch diskette read errors, would a period correct drive do better?

#19

Another comment mentions a KryoFlux. A cheaper alternative is a GreaseWeasel (£30, $30). The 4.1 version even has USB-C as a connector. You will need an external power brick with a 4pin Molex connector for 5.25 drives. You can buy these standalone or they might come with a SATA/PATA/IDE Hard Drive to USB converter. Can also use an old PC power supply if you fake the power on signal. I've had quite a lot of success, a…

kinda crazy that just switching drives can make an unreadable disk readable makes me wonder how many old floppies got written off as dead when it was really just an alignment mismatch

Re: Ask HN: 3.5 inch diskette read errors, would a period correct drive do better?

#20

Another comment mentions a KryoFlux. A cheaper alternative is a GreaseWeasel (£30, $30). The 4.1 version even has USB-C as a connector. You will need an external power brick with a 4pin Molex connector for 5.25 drives. You can buy these standalone or they might come with a SATA/PATA/IDE Hard Drive to USB converter. Can also use an old PC power supply if you fake the power on signal. I've had quite a lot of success, a…

kinda crazy that just switching drives can make an unreadable disk readable makes me wonder how many old floppies got written off as dead when it was really just an alignment mismatch

In the early 80s this was a fairly common thing that was known to happen with floppy disks where some manufacturers drives could not read disks written by other manufacturers even though in theory they were compatible and used the same standard. Usually floppy drive manufacturers test their drives against diswritten by whoever made the computer. So if you had an Atari, then anything written with an Atari drive could be read by any other drive you could connect to your Atari computer but if you had off-band drive, even if it was otherwise a good drive, there was no guarantee that a different drive could read that. This problem really came to head when manufacturers started going into different density drives. The early double density drives often didn't work with anyone else's drive, so when higher density became common, you really saw a lot of problems because people were trying to share this written by different drives. (and then there was Atari's oddball enhanced density drives that nothing could deal with for a few years.) you saw the same thing with Apple, Commodore, and probably with the PCs too, but I didn't know anyone who had those.

Tape drives were even worse for a long time. In many cases in the 80s and even into the 90s, sometimes a different drive from the same manufacturer couldn't read your tape.

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