Replacing MicroVAX II PSU With a Modern PSU

[Jon Elson]

On 11/24/2015 05:52 PM, Mark Wickens wrote:
> I haven't looked into this at all and I suspect it's probably quite tricky
> indeed. I did look around a while back drew a blank.
>
I built up a Micro-VAX II system out of boards, backplanes 
and assorted junk.  I made my own power supply.  The power 
supply is actually easy, just +5 and +12, with a touch of 
-12 for serial I/O.

The only tricky thing is the power-OK and reset logic, which 
really wasn't all that tricky, either.

I had a power and thermal safety control panel on it 
repurposed from the original 3rd party IBM mainframe memory 
box that would shut it down if there was an abnormal voltage 
or cooling failure.

Jon