stepping machanism of Apple Disk ][ drive (was Re: Heatkit 5 1/4 floppies)

My contempt for Apple begins and ends with their total disregard for the value of your data. If you wrote to their floppies, especially if your computer was in the "front room" of a business, exposed to whatever dust was carried in by customers and wind, etc, from the parking lot, (I had a client years ago, whose mail-order business was operated with the "help" of an Apple-II with two controllers and three drives in just such a location.) you'd frequently observe the computer locking up because it had come to a bit it couldn't read. The reason was probably contamination of media or drives, but the only recovery was the reset. Your data, meanwhile, and perhaps your customer calling long distance, were gone by now. They designed the MAC with no memory parity assuming that you'd not mind if your data was corrupted without your knowledge, and though the disk handling was a bit more mature than the Apple-II "I give up . . . and die" it wasn't much better.