> One of my 2100's has developed a problem. It was working fine for some time,
> but was only powered up occasionally. The problem started when I ran some
> burn-in diags over several days. The machine started acting funny, and when
> I powered it off and back on, there's no front panel display at all - no
> lights. However, all the fans come up, one of the internal boards that has
> an on-board led is lit, and I checked all the outputs of the power supply
> and they're just peachy. I moved every single card (including the front
> panel) from the bad system to another system and it then runs fine so I know
> it's not any cards. I suspect the power supply, but as I said all the
> outputs appear good. Gawd I hope nothing happened to that wire-wrap
> backplane.
>
> Can anyone offer some advice? I'm starting to pour over the schematics on
> the power supply - wondering if something is amis with the poweron or
> powergood signal perhaps but I don't know much about it.
>
My experience when I worked at an HP2100 site was that about 50%
of the problems had something to do with the backplane. You
probably don't want to hear this :-). Check for dirt or dust
in the connectors. One of the things the service people did when
they got strange problems was vacuum out the entire backplane.
For some reason HP2100s suffered more from bad backplane connections
and dirt than other machines I've used.
If a quick clean of the backplane doesn't work, its probably
a good idea to check to power supply (its easier) before going
back to the backplane for a more careful examination.
--
Dr. Mark Green mark_at_cs.ualberta.ca
Professor (780) 492-4584
Director, Research Institute for Multimedia Systems (RIMS)
Department of Computing Science (780) 492-1071 (FAX)
University of Alberta, Edmonton, Alberta, T6G 2H1, Canada
Received on Sun Feb 27 2000 - 11:47:46 GMT