[TUHS] Booting PDP-11's from RX02's

Pete Turnbull pete at dunnington.plus.com
Mon Oct 31 10:00:36 CDT 2016

On 31/10/2016 13:55, Noel Chiappa wrote:
> I wonder why DEC did't use track 0. The thing is small enough (256KB in the
> original single-density) that even 1% is a good chunk to throw away. Does
> anyone know? (I had a look online, but couldn't turn anything up.)
> If I had to _guess_, one possibility would be that track 0 is the innermost
> track, where the media is moving the slowest, and as a result it's more
> error-prone.

Except that track 0 is the outermost track, where the media is moving 
fastest, and therefore perhaps the least error-prone.  Except that for 
many drives, it's where the heads end up after a reset or recalibration, 
and on drives where the heads are (almost) always loaded, the one that 
will wear most.  I've seen floppies with a transparent ring near the 
outer edge, and I'm sure many other listmembers have too.

Pete Turnbull

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