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

28 pointsby rietta2 days ago32 comments

My first attempt at restoring 1991 Learning Company Spellbound for DOS for my children is dubious. Despite being stored nowhere near magnetic sources, there are read errors on the 3.5 inch floppies and Linux could not mount them. ddrescue extracted data but I have not confirmed it works. The box also have 5.25 inch disks but I do not have a reader online at the moment, that is its own project.

My technical question is this, the USB 3.5 inch drive I have is a "USB Portable Diskette Drive" that was Made in China but has no obvious sponsoring branding. If I take the time to bring back to life a more period correct system with an actual IDE floppy drive would it read the disks more accurately?

My goal is to get more of this good DOS and early Windows educational software working for my children. This particular title is meaningful because I have the actual boxes and learned on it myself all those years ago.

One option for hardware is my parent's Leading Edge WinPro 486. The case looks to be in good shape but I have not opened the case to see the condition of the capacitors yet. It has a natively mounted 3.5 and 5.25 inch drive.

sgbeal 3 minutes ago

> My first attempt at restoring 1991 Learning Company Spellbound for DOS for my children is dubious. Despite being stored nowhere near magnetic sources, there are read errors on the 3.5 inch floppies and Linux could not mount them.

FWIW, it's long been my experience that floppies (like CDs and DVDs) have a half-life and they degrade quickly upon reaching it. You'd have been lucky to be able to recover those in 2001. Now? If at all, only high-end forensic tools could recover them.

snvzz a minute ago

3.5" Floppies are either DD or HD. (there's more but let's keep it simple and practical)

A DD drive reads and writes DD floppies better than an HD one, but does not read/write HD floppies at all.

There's a hole in the floppy for write protection (hole covered = write enabled), and there's another hole on the opposite side to signal the floppy is HD. If it's covered, it is DD.

To recover a floppy, a USB drive is about the worst option, as they only expose a decoded floppy, and not the raw data, besides other annoyances.

You'll want a period correct HD FDD, or DD if your floppy is DD and your HD drive is having trouble with it, alongside GreaseWeazle[0].

0. https://github.com/keirf/greaseweazle

vunderba 2 days ago

Learning Company software has been pretty well archived at this point. To me, the easiest approach would be to hold onto the original box/packaging for sentimental purposes, and just find a copy of it on a site like the Internet Archive.

If your goal is to use it on a period-correct system, I’d go with 34/40pin adapters that lets you read flash cards, USB, etc.

A lot of my friends have kept their old 486 computers, and everything is period-correct except for the hard drive and floppy drive which have been replaced with a CF-to-IDE for the HDD and Gotek running FlashFloppy firmware for the 3.5".

PaulHoule 2 days ago

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-...

rietta 2 days ago

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.

fuzzfactor 8 hours ago

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.

worthless-trash 4 hours ago

It may be easier, instead of a serial cable, use a IDE hard disk drive.

You can still purchase IDE USB caddies for your modern system to write to.

mccoyc 6 hours ago

I can also recommend the KryoFlux. I had some floppy diskettes from a /very/ obscure computer, a Devtronix Model 264 pipe organ computer that recorded artists live, that also used the 3 1/2" form factor. It was able to completely recover all the data from them, and combined with the HxC 2001 Floppy Emulator, get everything onto a modern SD card format.

https://hxc2001.com/floppy_drive_emulator/

snvzz 7 minutes ago

GreaseWeazle[0] is where it's at now. KryoFlux was all we had before, but GW has overtaken it, and is open source proper.

0. https://github.com/keirf/greaseweazle

JoshTriplett 8 hours ago

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...

ssl-3 5 hours ago

> If I take the time to bring back to life a more period correct system with an actual IDE floppy drive would it read the disks more accurately?

It's worth noting that floppy drives (with rare exceptions like the LS-120) do not usually have IDE interfaces. In the PC space, floppy drives instead use, well, floppy interfaces. They're completely unrelated to everything that is IDE. (More specifically, they use floppy interfaces that are based around what the Shugart Associates used in the 1970s with their SA400 floppy disk drive -- but ~nobody says it like that.)

> One option for hardware is my parent's Leading Edge WinPro 486. The case looks to be in good shape but I have not opened the case to see the condition of the capacitors yet.

Cool! Way back then, we tended not to have so many problems with electrolytic capacitors. Boards didn't tend to use so many of them and the capacitor plague was not yet a thing.

It's possible that my risk profile is misaligned, but: I'd start by just turning it on and seeing if it works.

Feed it some floppy disks. See if they read.

If it shows positive signs of life, then: You can try your copy of Spellbound.

If that works, then: You can use the old machine to transfer the software to a newer machine. Methods vary (and that's a few steps out), but they usually involve the serial port on the old machine and a USB to serial adapter for the new machine. Sometimes, with a null modem adapter. (It's kind of a whole thing...and it kind of was way back then, too.)

kazinator 9 hours ago

Your idea is sane. You're already facing the problem of degradation of magnetic media; compounding it with dubious hardware isn't helping. Why can't that disk be read? Is it the disk, or this drive of dodgy origin? Or some combination of both?

An old drive will likely benefit from some cleaning: head, contacts.

rietta 8 hours ago

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.

VogonPoetry a day ago

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, almost 100%, over quite a long time - both 5.25 and 3.5. I did use older drives intended for "desktop" machines. The drives from Japanese companies seem to be the most reliable; NEC, TEAC. The 3.5 USB Portable diskette drives are based around laptop floppy designs. You won't be able to find a direct 5.25 to USB adapter (or modify one to work) as the speeds / data rates are all wrong, so you will need something like a GreaseWeasel or old PC for those.

I've used different reading mechanisms over the years; an old PC running Linux with a real floppy chipset + custom raw reading code, custom hardware with an F82077 + Atmel + SDCard, and most recently a GreaseWeasel.

The floppies I've recovered were stored relatively well, but were mostly my and family members data - not commercial floppies. If there is any copy protection on the floppies you are trying to read you may need to capture the flux transitions. For these, I'd check archive.org to see if someone has already generated a copy.

For 5.25 floppies fingerprints and surface blemishes can be softened / removed with ISO Propyl and a Q-tip. Floppies designed for cleaning the heads of drives seem to now be very expensive / non-existent. Manually cleaning the heads of a 3.5 drive is way more difficult. I've got ideas about using Face mask / filter material to create a cleaning tool, but it is on the experiments to try list.

Even back when floppies were a thing, I found that 3.5 drives were more un-reliable between machines than 5.25 drives. I think there was more variation in head alignment and track positioning. When I've had issues, I've always been lucky in that switching the drive vendor / model made reading the floppy possible even if it took multiple attempts or was very slow.

Good luck.

MoneyLovesSpeed 7 hours ago

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

bluGill 7 hours ago

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.

kevin_thibedeau 4 hours ago

The floppy interface for 5.25 is largely the same as 3.5. The data rates are the same. The only functional difference is fewer sectors per track because of the faster motor speed. That's all accounted for with a FDC interface controlled by a BIOS that knows what each drive is. A USB FDC bridge is stuck on its firmware and has no way to adapt to alternate track layouts it isn't designed to handle.

rietta 7 hours ago

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.

YZF 8 hours ago

It's hard to say. If the disk is borderline it's possible for it to be readable in one drive and not another. I have a couple of working machines with 3.5 inch drives so maybe ask around if a coworker or someone else you know has? I've read diskettes older than that but you never know. GreaseWeasel mentioned in the other comment might help as well.

hackshack 8 hours ago

An LS-120 mechanism (see "SuperDisk"), being designed for much higher density, can sometimes read the data.

M95D 3 hours ago

Unobtainium.

toast0 3 hours ago

There's several listings on eBay. The listings for laptops are in a range I'd consider...

The tricky bit is usually there's a proprietary connector for the specific laptop, but I recall taking a laptop cd drive for another project and it was basically a drive with standard 44 pin mobile ide connector plus a little board to go to the proprietary connector wrapped in a line specific case. I'd guess the ls-120 drives are the same deal.

Back in the day when I had an ls-120 drive, it was much superior to a regular floppy drive for reading floppy disks. So I'd definitely try to get that going as a first step.

jonhohle 6 hours ago

If you're patient, you can find a PC with a floppy drive at a thrift store/goodwill for $10-$15. In my area, I see them several times a year. I have a handful of USB floppy drives, one IBM, one generic drive from the Bondi blue iMac era, and both have worked about the same.

I've had a few discs fail with sector errors that have done nothing but sit in storage for 30 years. In that case, it was fortunate enough to contain a hidden duplicate of the file for the installer to copy.

freediddy 6 hours ago

The diskettes are going to demagnetize over 35 years, I don't think a 90s disk drive is going to make a difference.

bityard 6 hours ago

Maybe, maybe not. Floppies were always on the verge of dying all the time, even in the 80s and 90s. It's why anyone who cared about their data always had at least one backup copy of any important disk or data. (Most software explicitly told you to make a copy for regular use and keep the original safely stored away.)

GJim an hour ago

> Floppies were always on the verge of dying all the time, even in the 80s and 90s

THIS!

Gen-X here..... 3.5" Floppies were notoriously unreliable, even good quality branded discs had a fairly high failure rate. Were were always careful to make multiple backups of anything important stored to floppy. When CD-Rs came along they were a godsend.

Yes, a different drive might help OP as sometimes the alignment was slightly off between floppy drives (meaning data recorded on one would not read very well on another and vice versa). Although frankly, I'm not in the least surprised a 30 year old disc has gone titsup.

OP would be better to grab a copy of this data from archive.org or elsewhere if he can.

codazoda 7 hours ago

My guess is the disks or drive are bad. I have a similar modern Chinese USB 3.5” floppy drive and a box of disks from the 80’s and most of them seem to work fine in that combination.

LorenDB 8 hours ago

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.

piratebroadcast 8 hours ago

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

toomuchtodo 5 hours ago

Copy That Floppy – Cambridge guide for preserving data from fragile floppy disks - https://news.ycombinator.com/item?id=48827092 - July 2026 (71 comments)

https://hackaday.com/2026/07/07/its-now-imperative-that-you-...

https://www.digipres.org/the-floppy-guide/

anenefan 2 days ago

Old diskettes can be a problem especially storage that suits the white menace bacterial / fungus that can grow on the surface and cleaning can sometimes remedy but unless it's spots that can be got though the window with an ear bud, disassembly is required.

The thing I'd recommend is search of an image of the disks if they exist. Next best is an emulation eg [1] [2] which I found by way of google and yandex

[1] https://www.abandonwaredos.com/abandonware-game.php?abandonw... [2] https://archive.org/details/super-solvers-spellbound-dos-en-...

dfxm12 6 hours ago

My goal is to get more of this good DOS and early Windows educational software working for my children.

FYI, you can play in the browser on Internet archive: /msdos_Super_Solvers_Spellbound_1993

That meets your stated goal.

A more fun solution might be a Mister. If you're unfamiliar, it's like a hardware emulator. I've been playing gizmos and gadgets on it. If you really want the feeling of swapping disks, I have my Mister installed in a Macintosh iisi case asking with an nfc reader. I put nfc tags on old blank floppies so that when I insert the disk into the case, the nfc reader reads it and software (zaparoo) loads the game based on the tag...