mcfly that is exactly the info i was looking for, thanks a lot! Are alignment diskettes specially made or is it possible to make one yourself with a disk image and a working drive?

Nprod wrote:

mcfly that is exactly the info i was looking for, thanks a lot! Are alignment diskettes specially made or is it possible to make one yourself with a disk image and a working drive?

Not a chance, or at least I don't know a way to do it at home. These are very precise disks, hence the huge price tag on them then and even more now. What you need is a formatted floppy disk formatted in a working drive. I looked through the manual for my Panasonic drive and I can tell that there are some more settings that would require oscilloscope, for example index burst settings by adjusting index sensor position or a position of zero track sensor - if you want it factory precise. As I said before, for home purposes this is a good as you can get and after applying this on some good working formatted disk, I was able to read all the disks I got in my possesion. Interestingly, this procedure may also be used to read the floppies from drive with misalligned headers - for recovery purposes mostly, so having correct numbers for IMDisk you are able to do it and then re-set up header again so it will read all floppies.

Vaudane wrote:

As irritating as it is to say, it's not unlikely that all your disks are bad. […]
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As irritating as it is to say, it's not unlikely that all your disks are bad.

I ordered 10 3.5" 720 kB floppies from a seller on Ebay, and I checked them in a modern computer with Debian and a floppy drive. 7 of the 10 disks the drive couldn't detect at all, 1 had bad sectors, and 2 were fine. 70% total failure rate in other words (of a small selection I know) and 5.25" floppies are older and more delicate than 720s.

Could be worth getting a strong neodymium magnet and wiping it across one of your floppies. Make sure it's a strong magnet. Basically what you're trying to do is remagnetise the media (google magnetic hysteresis for more details). "Wipe" the magnet slowly over the disk, turn the disk over, wipe over other side. Repeat a few times and then try the disk again.

This is of course assuming there' s nothing on the disk you want, as this will completely destroy all data/sectors/anything else on the disks.

my friend have reported that the demagnetizing coil have helped (50Hz). Helps even to the boot sector errors and bad sectors, when just erasing the floppy just like the ordinary TV screen or magnetic cassette. Try.

IN general the side note.

Also, here I have aprox 4 drives: EC5323.01 (made in bulgary) which may be in interest. So far untested.

I am trying to resurrect an old 5.25 drive. If I remember correctly, this drive came from a Leading Edge Model D2 ( 386dx 16 ) from in 1989.

Much hair from long deceased cats was removed. I swabbed the heads with isopropyl.

The bent capacitors look like they are just bent. Leads are not broken, capacitor guts are not eviscerated.

I'm up to the point where the motor spins, the heads seek, and the drive gets detected during the floppy drive seek on boot. All promising.

However, the drive won't read or format disks. I get 'Invalid media or Track 0 bad - disk unusable'

Any suggestions for the next step? Head alignment? https://vswitchzero.com/2018/05/07/5-25-flopp … rive-alignment/