Rotating memory data recovery

[John Foust]

At 04:00 PM 9/15/2004, Tom Jennings wrote:
>I do not consider myself a magnetic-media expert, but I've made a number
>of (low-density) controllers and en/de-coding schemes, and repaired
>others, and read a lot (in one ear out the other probably).
>I figure there are a few failure modes that would be easy for amateurs
>(like me) to recover, like low-gain, dissipated magnetics (grain
>randomization, etc), and such, that would be amenable to software
>repair.

With platters, there are clean-room issues as well as very
difficult alignnment issues - imagine how difficult it would
be to re-align a read head with the concentric bands on a
platter that may have been slightly misaligned from its 
original hub, especially at contemporary densities.  
Floppies are a different matter.

- John