[comp.sys.mac] Disk recording format

bates@ssdevo.dec.com (Ken Bates DTN 522-2039) (12/10/86)

Does anyone know what the recording technology is for the 3 1/2" drives? i.e.,
how are the ones and zeros actually encoded on the disk surface from the
standpoint of magnetic flux transitions (NRZI, Manchester, etc.). Although it 
may seem like a relatively silly question, I'm writing a program which wants
to test the media surface for various reasons, and a comprehensive test must 
of necessity be based on the recording technology used. My local Apple service 
tech didn't know what I was talking about, let alone the answer to the 
question, so any help would be appreciated. Larry?

    - Ken Bates