Yeah, there were a few CDC drives like that ... I encountered a few "Hawk" drives once on an old Alpha Micro S-100 machine long ago; I believe it was, five megs fixed, five megs removable?
The pack was about the size of a garbage can lid and I believe the unit spun them up to around 2400 RPM or so ... Those are the oldest, largest magnetic disk drives I have ever seen in operation and it was very impressive to me at the time! So loud just running and a very definitive "clunk" from the head assembly when it started moving! Best, Sean On Mon, Jun 8, 2015 at 11:31 AM, tony duell <a...@p850ug1.demon.co.uk> wrote: > > > The RC25 was one of the last cartridge drives (before fixed drives came > back in small sizes and exploding > > capacity), somewhat interesting because of its compact size, and very > odd and hard to use because the > > designers threw in a fixed platter. Perhaps they thought that it was a > good idea because it gave you double the > > capacity at modest extra cost, but in practice it made for a major pain > in the software and operationally. > > Many other compainess pulled a similar trick... > > The CDC 'Phoenix' (is that a 9648 or something) had a removeable pack > containing one platter and > 3 fixed platters. Capacity was 16MBytes per surface (or so), so the > removeable pack stored 16Mbytes) > (one data surface, one servo surface), the fixed part was 80 MBytes (5 > data, 1 servo surface). > > Plessey made an RK05-a-like (same interface, linked to their version of > the RK11-D, took same > cartridges, same format, etc) with a fixed platter as well as the > cartridge. Of course the HP7900 was > like that too. > > I never really liked the idea. The main problem was you lost access to the > fixed disk(s) while changing the > removeable one. > > -tony >
