[NTLK] MP2100 repair, help needed

[Matthias Melcher]

> On 22. Jul 2026, at 21:34, NewtonTalk via NewtonTalk <newtontalk at newtontalk.net> wrote:
> 
> I assume you've tried a brainwipe? Not actually making one, but starting it the usual way and not click on "OK"? I also assume that the power supply and/or batteries are OK? And that the ROM board in these Newtons is an original one?

I did try all combinations of resetting, holding buttons, exchanging ROMs, I checked the voltage from the power supply, it's ok, and even the 3.3V inside the Newton is there.

> 100% of dead capacitors I've ever fixed on 2x00 mainboards were caused by a non-Newton power supply. So recapping the boards might not yield the expected result.

I did remove the board entirely and measured all capacitors. They are all fine except the SuperCap that stores time and date. According to AI, this one can interrupt the startup process, so I ordered new ones.

And of course, after I reassembled everything, the Newton boot right up. It's nice that it does that, but I would have preferred to find the actual issue. I assume that measuring all caps has resurrected something on the board?! Anyway, I will replace the super cap on both machines. If the second one then boots up too, that was likely the issue.

At least they are cheap and easy to replace. I will keep everyone posted.

> I was just informed by my wife that we have a large wasp nest next to my Newton stuff. I'll check for details tomorrow. If I manage to get past it and grab my 2x00 box, I can send you replacement boards or working Newtons. Might be a good opportunity to wear my motorcycle stuff again...

Don't let them get under your helmet though!

Thanks for the great offer. Right now, one of the machines came back to life, and I am hopeful that I will get the next one back as well. So I am covered for now ;-)

 - Matthias