On Tue, 18 Jun 2013, Jim Brain wrote: You're quite welcome, glad to help! Yes it should! I'd pull the drive and see if you can spin it by hand. If I remember correctly, there's a hole in the center of the drive's logic board that would allow access to the bottom of the spindle. Try powering up the drive and then give the spindle a shove with a jewlers screwdriver or other tool. Might have a stiction problem. The guys that created the FreHD hard disk emulator for the TRS-80 Model III and 4 are working on making it work with a Kaypro 10. Hopefully they'll have results soon. g. -- Proud owner of F-15C 80-0007 http://www.f15sim.com - The only one of its kind. http://www.diy-cockpits.org/coll - Go Collimated or Go Home. Some people collect things for a hobby. Geeks collect hobbies. ScarletDME - The red hot Data Management Environment A Multi-Value database for the masses, not the classes. http://www.scarletdme.org - Get it _today_!

On Tue, Jun 18, 2013 at 1:29 AM, Jim Brain <brain at jbrain.com> wrote: I don't know the Kaypro10 specifically, but unlike with some types of later drives, the ST225 should "just spin up" when power is applied. On common thing to the ST225 (and ST251 and others) is "sticktion". The heads could be "glued" to the platters by the lubricant that was used to prevent/minimize damage when the drive was spun down and the heads landed. I've personally had luck powering up stuck drives on an extended power cable (to give more elbow room for what's to follow), then holding the drive by the corners, platters parallel to the floor, pulling one hand close while pushing the other hand away with a "snap" action. It's a single impulse, meant to give a kick to aid the motor. If the heads are stuck but everything else is functional, this motion often frees things long enough to copy the data off before retiring the drive. I certainly wouldn't keep single copies of valuable data on a drive that had stuck once since it's nearly guaranteed to happen again. Back in the day, the short-term solution was to not turn the box off so the heads wouldn't land and stick again. Fortunately, in the world of ST412-interface ("MFM") drives, the ST225 was one of the single-most popular models manufactured. Unfortunately, many of them logged a lot of hours and died or are not that far away from dying, so even a replacement drive is a hit-or-miss prospect. I haven't worked with hard drives in Kaypros, but drives of this type in the 5MB-80MB were what PCs had from the XT on up until they started shipping with IDE drives (except for the less-than-mainstream machines that had ESDI, SCSI, or, rarely, SMD drives). The formatting software would be unique to the platform (and possibly the controller as well), \ -ethan

AFAIK The ST225 (like most, if not all ST412-interfaced hard drives) should spin up as soon as it gets power. There is no interface cable signal ot control the spindle motor. Sicne the rest of the machine is working, it's likely that hte power supply rails are all present and correct, but it can't hurt to put a voltmeter on the hard drive power connector just to check. The middle 2 pins are gorund, expect +5V on one of the outside ones and +12V on the other. However, ST225s are notorious for stiction. The heads stick to the platters nad the thing can't spin up. WIth nothing to lose (the drive doesn't work anyway), try removing the logic board from the drive and rotating the spindle motor in the normal direction of rotation (I think that's counterclockwise, seen from the PCB side of the HDA). Most likely it will seem to be stuck. If you give it enough force it will move, hopefully by freeign the heads from the disks, if you are unlucky it'll rip the heads off, but the drive was dead anyway... If you can get it to turn, refit the logic board and try to boot the machine. If it works, at least you know the controller is working. -tony