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Profile Hard Drive: Info, Maintenance, and Formatting by Patrick Schaefer (March, 2000) supplied by Dakin Williams Good news first: everything in a Profile is serviceable. The drive mechanism is a regular Seagate ST506/412 (IBM AT drive), the electronic components can be checked by swapping into a working drive. First the boards, then single chips. Maintenance Although ST506 mechanisms are, naturally, rather noisy, you can probably reduce noise on a Profile drive which has not been regularly serviced. You can disassemble the profile, remove any dust located under the analog pcb and put a drop of oil on the tip of the copper spring that touches the spindle motor axis. Do not rotate the step motor and do not oil anything else! And of course do not open the drive unit itself. Reassemble the profile but do not put the cover on it. Connect it to the power line, switch it on and wait. After 18 seconds the stepper motor will move from its park position to track 77, then to track 0. After that, a surface scan of the disk is performed. You will see the step motor rotating slowly while the heads travel from track to track. Sometimes the heads jump to track 77, then the scan continues. This means a bad sector has been found. The drive does not access this sector, it uses a spare sector instead. There are located on track 77, 32 are available. Now watch the surface scan and count the number of movements towards the spare track. A new drive uses 0..2 spares, 3..5 is means fine condition. With more than 10 spare sectors used you should look for someone with low-level formatting tools. The main problem with these older drives is that information stored on magnetic disks fades after several years. The data sectors are rewritten every time you store something on the disk. But the address field headers are not. They were written in the factory and never changed since then. If a couple of header bytes fail the drive cannot locate the associated sectors and it assumes they are bad. So you will get a lot of bad sectors reported, however your disk surface is okay. Low-level formatting rewrites everything on the disk. Low-level Formatting Formatting a Profile requires an Apple ///, some software and a special formatter chip that replaces the Z8 chip on the logic board. With the formatter chip Profile understands a new set of commands, then you can format the drive, do a surface scan and initialize the spare table.These formatting tools are very difficult to obtain, because there are still some people eaning money with them (the 'certified Apple technician'). In the US you can contact Steven N. Hirsch [shirsch@adelphia.net], perhaps he will do the formatting for you. Unfortunately Profile and Widget are the only drives that could be used with a Lisa 2 without any restrictions. SCSI drives are available from Sun Remarketing, but they require a driver to be loaded first, and this means you have to start up from diskette. Thererfore it is necessary to maintain these old machines as long as possible. Some time ago I have started disassembling the Z8 code and drawing a schematic diagram of the loagic board, but this hasn't been finished yet. I thought about designing a Widget emulator based on an IDE drive. I am still looking for some information about formatting Widget-10 drives Regards, Patrick