I recently posted to the IRC and was told that this would be better for the fourm.
I have two Disk II drives that power on but can't read. I'd like to restore full function in them. I've heard that there's issues with the belt melting in these old drives, and unless anyone guesses otherwise, I'm assuming that this is the issue. I'd go and open the drive to find out if this is the issue, but I know that floppy drives can require calibration if you mess around in them, so I want to avoid messing up calibration. Is this actually avoidable or can I replace the belt without any issue? If this does turn out to be the issue, where can I obtain a belt for it? I remember watching something years ago where the creator of the video just got a big assortment of differently sized belts.
You can open the drives (take the covers off) or replace the belts without affecting the calibration. It helps that there is a lot of empty space inside these drives and not much electronics.
Why are you certain the belt failed? I would deduce that to be a possible issue if:
1. spindle motor is turning and making noise (not the head stepper motor that is different)
AND
2. the "cookie" never moves inside the floppy sleeve when inserted and attempted to read
You can see if the cookie (the magnetic media) has moved by checking the position of the index hole punched in it.
If the belt is bad it looks like there are replacements available; you could also measure and look for a matching belt from the audio tape world of which there are many.
The motor is definitely turning. I'll check both of them later to see if the cookie is moving, but I'm pretty sure it's not iirc.
As to obtaining belts, would something like this do the job? I'd prefer to order from Amazon because shipping is free with prime and fast. If I need something more spicific I guess I can put up with one of the sites you suggested.
Well, I'm guessing this isn't a good sign. I lugged out my Apple II Europlus, and plugged the drives in. I stuck my DOS 3.3 System Master in drive 1 with the index hole at the spot where you can see it, booted it up, and it looks like it is indeed spinning. It doesn't autoboot nor does PR#6 work though.
Have you only tested both drives with one disk? Do you have any other disks to try? Also, have you tested both drives with the same disk II interface card? In my experience it's pretty rare for a belt of a disk II drive to have failed. Chances are, it's not the belts - but the disk, the interface card - or the drives' speed which needs to be adjusted.
Update. I pulled both drives apart with a buddy, and we were able to free one of them by rolling the head back to the start. The other one seems to step back 40 tracks but never moves forward to read. I'm guessing the stepper motor or something on the board is messed up.
In other news, after booting into dos with the functioning drive and messing around for a while, my filter compacitor let out the magic smoke, so it looks like I'll be rebuilding my power supply now. Luckily there was no pop so that should make things easier.
It's usually one of the driver chips or transistors that control the stepper motor inside the drive, or one of the driver chips on the interface card.
Hello,
I am in France and I can restore it (that is my "real " job)
Causes:
- PSU (bad voltage)
- interface card (chip(s))
Drive:
- capacitors
- chip(s)
- calibration of the head (azimut/speed)
My best
I'm guessing it's not the interface card since one drive works while the other doesn't in either spot. I'll figure out what chips are in the drive and control of the motor and I'll purchase new ones I guess.