24 Nov
2009
24 Nov
'09
7:37 a.m.
My expeirience is that if you have a drive with a
correctly-aligned
positioner/head assemly, you can remove it as an assembly, and put it
back in _the same drive_ and it will still be alighed. But if you move
positioenrs between drives you have to do a realignment.
In my case unfortunately that would not be the case as the best I can find
are two other units in unknown condition from a completely different set of
drives.
The alignment procedure is not hard if oyu have the
alignment pack. You
also need a 'scope (but just aout any 'scope will do) and a way of moving
the heads to a particular cylinder and selecting head 0 or head 1. I had
no prolems using a PDP11 + the appropriate controller for this, just
togging values int oteh controller registers from the PDP11's font panel.
If you use a PDP9/e, I think you have to write a trivial program for this.
I can easily get hold of a scope but a calibration pack is a different
story.
THe disk packs are different between the PDP8 and PDP11
systems. They're
hard-sectored (by notches in a metal ring on the disk hub), PDP11 packs
are 12-sectory, PDP8 packs are 16 sector. The former are _much_ easier to
find.
I think if I could find the rest of the system I might also find the packs
as well. Since this was a local and very little known recycling job only a
few businesses in town and university staff drop stuff off. I really wish I
knew dropped this off but alas, no records are kept on who drops off what.
My best bet is either the hospital or it came from someplace in the
university. Where exactly I have no idea.