osiweb.org

... work with a Altair 8800 FD controller, or are they specific to OSI?

I don't know much about the whole 8" drive thing.


https://www.ebay.ca/itm/254996424823?ul_noapp=true

They should work, if the drives are functional (the listing did say "SELLING FOR PART OR REPAIR"). OSI drives needed an extra circuit, the data separator, that most other systems didn't need, but its presence would not prevent the drive from working with other systems that didn't need it.

The "A" drive, in particular, should work without any modification. The OSI "B" drives generally had a small change made to the drive select circuit. I don't remember the details, but comparing the circuit boards on the "A" and "B" drives should show where a trace was cut on the "B" drive and jumpered somewhere else. Restore it to the same condition as on the "A" drive and use the drive select jumpers to designate which is "A" and which is "B".

I think the 8" drives provided separate clock and data already, which is why OSI took the easy route and used a 5.25" drive that had an option for a data separator as well, rather than redesign their disk interface.

So any 8" drive that works in an OSI would most likely work fine in any other system.

Thanks for the input guys. Yes, I think you guys are right right. They should work .. if they are functional

However this the listing did say "SELLING FOR PART OR REPAIR" weighs heavily on my mind. I have a 100 sq. ft. storage room that is filled from floor to ceiling with "projects" in the queue. The last thing I need is another project that will take me 50 years to get to, seeing as I'm 64 already. So, these drives will not be coming my way.

I already have a solution for my Altair that can use a PC as a disk server. It will do up to 2 8MB disks too! Lots of room, and while not real metal, it will have to do for now.