I've had a stack of dead PB100's around for a while, so I started working on them.
After the usual recap of the logic board (there are a lot of them), I found some caps I had originally missed on the back of the LCD:
That was enough to get at least one of the machines up and working.
I put a CF PowerMonster II from artmix in it, but it seemed to not work. The problem is the PB100 leaves /RST and /TRM OFF disconnected. They're left floating on the CF PowerMonster II, which it doesn't like at all. I connected both of them to +5V, and the PB100 was up and running:
Next up was the battery. I had a dead 3rd party battery by BTI, which has a lid that screws on. After removing the lid, the battery contained a couple plastic bags full of lead-acid goo. After removing those, I put in a 7.2V 1000mAh AAA flat pack battery:
There's plenty of room left to add more than one pack.
And finally, here's the whole thing up and running on battery:
Terrific. For the record, that matches the version from the original non-backlit Portable, so both Portables and the PB100 use the same M50753 PMU code. (Each PB1xx generation after that revved the PMU code). Another dark corner documented
I just wanted to add to this... I know it's an old link... but something to be careful of with the 100's... Take the Trackball OUT when storing... The pressure put's those ugly "pink" blotches on the screen.. I've seen way too many damaged screens from the trackball pressing against it.. more so when it is stored.. and even more with weight ontop of it.. So just take the trackball out when storing or even closing it.. It's just the best thing to do.. And also try to store it vertically instead of flat.. that will avoid pressure on the screen to any of the stuff such as keyboard and mouse clickers.. The rubber bumpers on these machines are decaying and it lessens the clearance..