EX2000 Floppy Drive Tester

Ah, but that assumes that : The read chain is working The heads are well-enough aligned to read a given track The spindle speed is close enough for the data separator PLL to lock to the signal from the read chain If you're working on a defective drive, you can't assume any of those. The whole point of a drive exerciser (and I use one a lot) is that you can test each part of the drive separately. You can turn on the motor, look at the index signal. If it's missing, you look to see if the disk is rotating, and troubleshoot the motor or index circuits as appropriate. if the index pulse is there, you can set the spindle speed my measuring the frequency of said index pulse (although there's often a stroboscope disk on the spinde that you look at under a mains-powered flourescent lamp, and tweak the speed control preset so that the pattern appears to stand still (at least one manual I have gives a tolerance in terms of blocks passing a fixed point per minute). You are assuming the disk is readable by a PC controller. Which may well not be the case. One other advantage of the drive exerciser I use is that it's about the size of a multimter. Trying to set up a PC system and cable it to a drive I am repairing would be almost impossible. But the exerciser will fit onto my workbench surrounded by bits of classic computer. -tony