Kaypro successes

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