[SPARCbook] Power problems

[Matthias Granberry]

If you run a WELL-REGULATED 12v power supply to the battery
connectors, you can run it from the battery DC simply keep the battery
removed.  I don't know what to do about the nvram, though.  Good luck on it.

"Liam" <Liam1f at blueyonder.co.uk> writes:

> Hi,
>      I've got a problem with my SB3 TX  which I've made worse and don't know
> what to do next.
>    The original problem was that it stopped working when the charger was
> plugged in. It would / will charge the battery (which obviously runs down
> quickly) when plugged in and not being used, but would then only run on the
> battery with the charger still connected.
>    I have tried an original Tadpole charger, a HP one and my own bodged one
> with no result. They all, however, work on my SB3, SB3XP, PowerLite and
> PrecisionBook. (This might sound greedy, but I like the little beasts!
> Something about unusuality!) The TX being the higher spec. of the lot, I'm
> disappointed that this is the one that gave up.
>    On guesswork, I have checked voltages going to the battery terminals with
> the charger connected; to both the internal battery and the terminals of the
> external battery (even though I don't have one) and have 5v and 12v  (-ish) on
> some terminals.
>    Thinking myself clever by previously identifying damaged components on one
> of the boards of my XP, then finding out the values (straight from Tadpole, no
> less!) and finding someone to do an economical repair, I took the whole thing
> apart to examine the circuit board tracks. I am certainly no expert,  but
> there was no burning damage evident anywhere. At one stage, though, while
> poking and pressing connections with the charger plugged in, I'm sure I
> smelled burning. My wife says she didn't....but we don't always agree on
> things (especially computer related), anyway.
>    While I had the whole thing apart, (I can explain why I did it...I've got a
> Sun Ultra 5 that I had to change the NVRAM in, and got inquisitive) I took the
> 'SnapHat' battery off the NVRAM. I know this was not a clever thing to do. I
> know that I will probably end up putting the thing into a shop for someone who
> may understand the power problem to see, but is unlikely to recognise any
> printenv stuff. (Unless I want to pay a real fortune).
>    Any ideas would be gratefully recieved. I would really hate to write this
> box off.
>
>                                                                Yours in hope,
> Liam
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-- 
Matthias Granberry
matthias at utdallas.edu
(214)432-2384