Copying Mac Disks with a Single Drive

Tony Duell ard at
Fri Feb 9 18:10:36 CST 2007

> > What are the dimensions of the different size heads?
> >
> Not sure about dimensions- the 800/400k drives I think share common 
> dimensions with the PC-esque 720k drives, and the 1.4 SuperDrive is 
> known to be the same dimension as the 1.44 MB PC mechanism.

And AFAIK all those heads are the same size. All those drives (Mac and 
PC) record 80 cylinders) at 135tpi. 

There is no problkem moving (720K) disks between 720K and 1.44M drives 
(there was moving 5.25" 360K disks between 360K and 1.2M drives because 
the former is a 40 cylinder unit, the latter an 80 cylinder one).

There were a few 40 cylinder (67.5 tpi) 3.5" drives, but AFAIK they were 
never standard on Macs or IBM PC compatibles.


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