15 Sep
2015
15 Sep
'15
10:03 a.m.
On Sep 15, 2015, at 12:28 PM, tony duell <ard at
p850ug1.demon.co.uk> wrote:
...
AFAIK the RK04 never existed. The RK02 and RK03 were re-badged Diablo Model 30
drives, the 02 being low density and the 03 high density. The RK05, very well known
was a DEC drive of the same capacity, physical track format, etc as the RK03 (that is
'high density, about 2.5 MBytes on a disk).
There was also an RK08, as I recall -- same platter as the RK11/RK05 but 16 sectors per
track instead of 12.
If I remember correctly, that same 16-sector platter was used in the IBM 360 model 44
which had an RK05 lookalike built into the CPU cabinet (on the side). I never used it;
not sure if OS/360 supported it, that might have been PS/44 only. If yes, one wonders if
it was fixed size sectors, a rather un-OS-like thing to do...
paul