27 Feb
2000
27 Feb
'00
2:28 a.m.
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.
Any tips most appreciated!
Jay West
27 Feb
27 Feb
3:47 a.m.
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(a)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
6:45 a.m.
New subject: HP2100 help requested - minor progress
Dr. Mark wrote......
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.
I use a particularly fantastic contact cleaner designed for gold. I can't
say enough good about it. Now I use it on all cards and connectors I get
during the cleaning process. My backplane has been very babied :)
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.
Ok, I dug through some info on the power supply. It appears that the IPU
(Internal Power On) and PWU (power up) signals should go from 0 to 4vdc +/-
1v within 1/2 second of line voltage crossing 102vac. On my good machine
they do, on this one they don't. It appears now that there is a problem with
the A3 control board which monitors power and is the originator of IPU and
PWU. If the revs of the boards are the same I'll try switching them. In any
case, at least it seems to be isolated to one card.
Thanks for all who responded, I'll let the list know what I find.
Jay West
PS - who was it that had a 2100 for years and hasn't touched it? Aw c'mon -
give it a good home - I do know one ya know <GRIN>
7:41 a.m.
New subject: HP2100 help requested - minor progress
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2:02 p.m.
New subject: HP2100 more minor progress
Well, the bad card is definitely A3 in the power supply. This is the card
that checks overvoltage, undervoltage, and provides the powerup signal.
Unfortunately, my schematics for the power supply boards is correct for all
the cards except A3. My schematics are for 2100-60047 and my board is
2100-60109. Since the 60047 version has IC's and my 60109 board does not,
I'm a little hesitant to accept the schematic I've got. Sheesh! Also, how
come most HP power supplies I've worked with don't have ejection handles on
the cards? There always a major pain to remove (wiping off my bloody
knuckles <grin>)! Cursory probes with a transistor checker and vom don't
reveal the problem.
Unless someone here has schematics for the 2100-60109 A3 board, it looks
like I'll be calling a dealer tomorrow to find out just how much he'll
charge for a replacement board. Grrrrr....
Thanks to all who replied!
Jay West
28 Feb
28 Feb
4:50 a.m.
New subject: HP2100 more minor progress
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27 Feb
27 Feb
8:05 a.m.
New subject: Contact cleaner? Was: HP2100 help requested - minor progress
I use a particularly fantastic contact cleaner designed for gold. I can't
say enough good about it. Now I use it on all cards and connectors I get
during the cleaning process. My backplane has been very babied :)
Jay West
So don't keep it a secret! What is it and where do you get it for how much?
I've used Cramolin (red and blue) that I bought years ago for my audio
interconnects. I tend to use it as a general palliative and can't really
verify or dispute its effectiveness. How do you judge?
Bob Stek
Saver of Lost SOLs
bobstek(a)ix.netcom.com
2:24 p.m.
New subject: Contact cleaner? Was: HP2100 help requested - minor progress
Bob wrote...
So don't keep it a secret! What is it and where
do you get it for how
much?
I've used Cramolin (red and blue) that I bought years ago for my audio
interconnects. I tend to use it as a general palliative and can't really
verify or dispute its effectiveness. How do you judge?
It's made by Caig, and called Pro Gold G5. It cost me about $15.00 for a 5oz
spray can. I've used it on every gold connector in 3 restoration projects,
and I still have almost 1/2 can (and that includes scrubbing all the
backplane connectors with it). The only drawback is it is ONLY for use on
gold connectors. I use it on backplane connectors as well as the edge
connectors on cards with a very soft toothbrush.
How do I judge efficacy? It has definitely solved several problematic
connection backplanes for me. Also many I/O cards that were very hard to
seat now slide in and out effortlessly (and still seat snugly). Old very
worn connectors (and even corroded ones) come out bright and shiny almost
immediately. Supposedly it also prevents future corrosion. And best of all -
it's completely safe to get on plastics (although they do advise wiping up
excess quickly). When talking to a rep at the company, they also said it is
completely non-conductive and can be sprayed on live connections. I wouldn't
do that - but it does make me feel like I don't always have to let the
connector dry over 24 hours before using.
Regards,
Jay West
4:07 a.m.
New subject: HP2100 help requestedr
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4:55 a.m.
Jay,
Do all of those machines use the same power supply? I know where there
is a HP 12797 (or 12979?). It's an I/O extender for the HP 1000. It looks
like it has the same card rack and power supply as a 1000. I can probably
get it cheap if you need it. It has a DCPC card in it but all the other
cards look like interface cards for external IO.
Joe
At 10:28 AM 2/27/00 -0600, you wrote:
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.
Any tips most appreciated!
Jay West
9064
days inactive
9065
days old
9 comments
5 participants
participants (5)
-
ard＠p850ug1.demon.co.uk -
bobstek＠ix.netcom.com -
mark＠cs.ualberta.ca -
rigdonj＠intellistar.net -
west＠tseinc.com