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View Full Version : Which 8" Floppy should I buy for use on multiple CP/M machines?



VERAULT
January 22nd, 2018, 05:21 AM
I am interested in buying an 8" floppy drive for use on some of my CP/M based machines and my kryoflux. For instance my Access Matrix computer came with the 8" floppy connector option on it. Now I dont know anything about 8" floppy drives, I have never owned one before. I know like all floppy drives they can have multiple formats. So which one would be closest to a universal drive for more connectivity? The name Shugart tends to come up frequently when you search 8" floppy drives, but I see siemens as well. According to this page my access computer has a 50 pin connector for an 8" drive:https://ipfs.io/ipfs/QmXoypizjW3WknFiJnKLwHCnL72vedxjQkDDP1mXWo6uco/wiki/Actrix_(computer).html

I trust you guys with the knowledge on these, so please any info you have let me know. Thanks.

SomeGuy
January 22nd, 2018, 05:41 AM
For use with a Kryoflux, it is better to have one of the later 8" drives with a direct-drive motor rather than a belt-driven motor. These have a more stable rotational speed. (These are also usually half-height)

For use on an actual vintage computer, you will need to look closely at what signals are expected by the computer, and what signals are provided and jumper options are available on the the drive. The 8-inch "shugart bus" connector was not a rock-hard standard and may vary slightly from system to system. Most of the later drives provided numerous jumper options for compatiblity.

VERAULT
January 22nd, 2018, 05:43 AM
For use with a Kryoflux, it is better to have one of the later 8" drives with a direct-drive motor rather than a belt-driven motor. These have a more stable rotational speed. (These are also usually half-height)

For use on an actual vintage computer, you will need to look closely at what signals are expected by the computer, and what signals are provided and jumper options are available on the the drive. The 8-inch "shugart bus" connector was not a rock-hard standard and may vary slightly from system to system. Most of the later drives provided numerous jumper options for compatiblity.

So if these later half height drives have a jumper for compatibility wouldn't that be the best choice? I dont think I would be using the drive on anything made before 1980, although that may change one day.

Chuck(G)
January 22nd, 2018, 08:20 AM
For use with a Kryoflux, it is better to have one of the later 8" drives with a direct-drive motor rather than a belt-driven motor. These have a more stable rotational speed. (These are also usually half-height)

I'm not so sure--ISV on direct-drive 8" units is worse than the line-operated models, which employ a heavy flywheel to stabilize things. Since they are line-operated and use induction motors tied to the line frequency, if you're fed off the grid, that's not going to change. The only downside is the belt that's used--with age, it can begin to slip.

My impression of the direct-drive Tandon units, which are the most common is that they were considerably cost-reduced versions of the full-height models. I never liked those.

My favorite drives are the Siemens FDD-200 and the Qume DT/8.