18 Jan
2012
18 Jan
'12
11:05 p.m.
Richard wrote:
I'd advise you to consult with the folks at the
Living Computer
Museum. IMO, they did a wonderful job of replacing the original power
supply in their machines with a modern efficient switching design.
My
understanding is that they replaced the entire ECL power supply
system with modern switchers.
I plan to keep the original power supply front end (three-phase to -12V
DC), and only replace the linear regulator modules (nine each -12V to
-5.2V at 35A, and four each -12V to -2.0V at 35A) with switchers. That
preserves (and actually improves upon) the AC power-fail functionality
of the system, allowing the processor state to be written to RAM, to
allow resumption of execution on power restoration. (Assuming that the
RAM is nonvolatile, which in the original machines was accomplished by
either core memory, or battery-backed DRAM.)
However, I plan to get the machine working with the original regulators
before I change anything.
It was all done in such a way that the upgrade was
fully reversible to
restore the machine to it's original condition.
Naturally I plan to do that
also.