On 2021-02-11 10:55 p.m., Carlos E Murillo-Sanchez via cctalk wrote:
This decade seems to have increased the number of failing things in
such a way that the "to be repaired" backlog is growing much faster
than I can get to diminish it. Argh. A month ago my trusty HP9000/380
ran just fine and I booted the different OS's in the SCSI and HPIB
drives connected to it (this particular machine is interesting because
the 9000/300 port of NetBSD was partly developed in it: it was Mike
Wolfson's). Yesterday, it failed to turn on; the power supply is
dead. So I unracked the pile of drives and the computer, checked for
obvious things (the fuse is fine, and nothing in the power supply is
swelled up or leaking, or browned by heat; visually, it looks new; the
HV caps seem to hold a charge). I need the schematics for the power
supply (at least the output connector; I can work my way back from
that) and also those for the backplane in this hp9000/380. A
preliminary search at bitsavers and elsewhere did not help. Does
anybody have these?
In the meantime, I finally improved the mainboard (had the parts for a
long while) from a 380 to a 385 by changing the clock generator, and
replacing the 68040RC25 with an RC33.
I ran this machine as a web server continuously for ten years in the
2000's, totally exposed. Many tried to hack it... and failed. Another
personal connection to this architecture is that I used Apollos and
hp9000/300 at UW-Madison back in 1989-91. Boy, did I crunch numbers...
carlos.
I have never seen any schematics for this power supply however on
bitsavers there is a document related to the expander that shows the
power supply pinout.
http://www.bitsavers.org/pdf/hp/9000_300/specs/A-98568-66501-4_98568A_Schematic_Notes_Jun85.pdf
This would be the same power supply as the processor box. Also
http://www.bitsavers.org/pdf/hp/9000_300/specs/A-98561-66501-4_98561AB_Schematic_Notes_Jun85.pdf
Paul.
