"John B. Matthews" <nospam@nospam.com> writes:
>analog card inside the drive. I seem to recall folks saying it 
>blew the "read sense amplifier" chip, luridly recounting how it 
>would smoke and be visibly burned afterward. Is that the 
>"ULN2003" you mention?

The Read Sense Amp is the MC3470 IC. The ULN2003 is a high voltage, high current
darlington array IC used to drive the stepper motor phases.
-- 
David Wilson  School of IT & CS, Uni of Wollongong, Australia