16 Apr
2009
16 Apr
'09
6:44 p.m.
It's the
11/44 (a much later machine) that has odd fans -- 35V 70Hz or
something. They run off a transistorised full-H driver circuit in the
PSU, so they can be run off the backup battery.
I have some power supplies -- out of an IBM storage setup or similar -- that
use fans that operate on an odd voltage like that. I get the impression that
they chose that voltage as being the maximim input for some 3-terminal
regulator part on the other end.