[NTLK] MP2100 repair, help needed

[Greg Toffer]

Could it be that one or more of the connectors on the board were oxidized and removing and plugging them back in removed that layer just enough to make the Newton work again?

Daniele

Il giorno 23 lug 2026, alle ore 11:14, Matthias Melcher <mm at matthiasm.com> ha scritto:



> On 22. Jul 2026, at 21:05, Greg Toffer <gregtoffer at hotmail.com> wrote:
> 
> Hi Matthias,
> 
> could it be the Crystal oscillator? Or maybe the very few electrolytic capacitors still presents on the board.
> 
> Daniele

The oscillator is oscillating according to my oscilloscope. I do measure the 7.2V form the power supply and even the 3.3V on the CPU rail.

There is only a single electrolytic supercap which is indeed almost dead. It keeps the time and date chip running. At the very low chance that this chip throws off the boot process, I ordered new supercaps. They are easy to reach and replace.

After disassembling everything and measuring each capacitor, putting it all back together, it finally booted. This is nice, but I would much rather have found the problem.

I will keep everyone posted on the list.

- Matthias
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