On Sun, Mar 23, 2025 at 6:30 PM Ali <[email protected]> wrote: > > > I don't have any spares for these drives. As I said earlier you need > > to know the complete model number to get the right drive to take parts > > from. It does have to be a -B (double head, 48tpi). The -A is > > single-head, the -E (very rare!) and -F are the single and double head > > 96tpi versions, so the head is designed for a narrower track. > > What is so special/rare about the E? I have only seen the -B and -F variants > used in most machines.
A = 40 cylinder single head B = 40 cylinder double head E = 80 cylinder single head F = 80 cylnder double head. Very few machines used an 80 cylinder single head drive, and I suspect the -F wasn't much more expensive anyway. So the -E model is not at all common (I believe C and D were reserved for 77 cylinder (8"?) drives, G is 80 cylinder double head, high density (360RPM? -- 1.2MByte), and H is 80 cylinder double head high density (1.4MByte)) -tony
