Question on DEC file formats - test-drb@ccmp.vtda.org

15 Jul 1998

...
 Do there exist DEC drives A and B such that A and B
have their own
(different) 'native' packs, and packs from A can also be read (at least) 
in B, but not vice versa 
I don't know of any such disk packs (in fact, there is one combination,
I forget which, which will result in a volume spindle swedged into the
drive spindle -- making the drive so much worthless hardware)

However, TK50 and TK70 fit the bill... you can read TK50s on a TK70,
but not write them.  Tapes written on a TK70 cannot be read on a TK50.

					Megan Gentry
					Former RT-11 Developer

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