10 Aug
2005
10 Aug
'05
2:39 a.m.
The disks have a "-8" designation on the
edge, where the RK05s have
the -16.
I'm guessing this is the count of number of sector pulses per revolution
of the pack. There are notches on the hub that generate these.
PDP-8 RK05's are 16 sectors, PDP-11 RK05's are 12 sectors.
I don't know about the RK01, but the RK02 through RK05 (excluding
RK05F) all present the same geometry.
In non-DEC uses, I believe there were 8-sectored packs in common use.
Tim.