On 09-Feb-2002 Tothwolf wrote:
> On Sat, 9 Feb 2002, Thilo Schmidt wrote:
>> On 09-Feb-2002 Tothwolf wrote:
>>
>> > I've used a dremel tool to cut/grind away carbonized areas of boards
>> > and replace it with new material or wire jumpers.
>>
>> Good point, when I'm at the university next week, I'll try to remove
>> the charred areas around the diode.
>
> Well, unless you know for sure that the area is indeed carbonized, and
> that is causing a problem, you should leave it alone. Usually this only
> causes problems for high voltage or highly sensitive parts of circuits.
Of course I don't think the charred area is responsible for the PSU failure
... it wasn't even there when it failed ;-)
But it may become a problem later, so I'll check if the resistance is way
below
a few mega Ohms and clean it if necessary.
> I imagine something else took out that diode, which is still causing your
> problems with the supply.
Maybe that's true, but maybe the diode was there to protect something
that got damaged when the diode died. Or even worse the HP9000 got
damaged...
But the beast is old, there are a lot of possible points of failure inside
and I don't even know how the PSU behaved when it was still operational.
If I could figure out if and how the PSU interacts with the computer I could
put another PSU in the case. But without that knowledge I'm stuck :-(
bye
--
The most exciting phrase to hear in science, the one that heralds new
discoveries, is not "Eureka!" (I found it!) but "That's funny ..."
-- Isaac Asimov
Received on Sat Feb 09 2002 - 15:58:25 GMT