Drives which used an MC3470A head-amp

Hi guys, As you might have gathered from my other thread, I'm toying with the idea of building a replacement controller card for my two dead double-sided Amstrad disc drives. Ideally I'd like to use as many "standard" parts as possible to ease debugging and future repair. I'll probably use a GAL to handle head-stepping and the write protect lockout, and LSTTL for the bus interface. I'm also planning on adding an overvoltage crowbar (or maybe some form of a MOSFET OVP switch) on the 5V rail to protect against the common killer of these drives: plugging them into a PC PSU (the power plug is a Berg floppy power connector, but with a mirrored pinout). I've got my hands on a couple of Texas Instruments MC3470A floppy disc read amplifier ICs, and the Apple Disk II schematics suggest how this can be tied to a drive mechanism. What I'd like to do is look at a few other drives which use this chip to make sure I understand everything correctly (a double-sided drive with a single 3470A would be handy). If I'm being honest, the TI datasheet for the chip is utter crap... So does anyone know of any other FDDs -- besides the Disk II -- which used the MC3470A as the head amplifier, or maybe a few applicable application notes? Thanks, -- Phil. classiccmp at philpem.me.uk http://www.philpem.me.uk/