[NTLK] Capacitor Replacements?

[Victor Rehorst]

I can try to help with that.

Frank helpfully posted his draft OMP/100 disassembly instructions a few 
years ago here (link to a Word file at the bottom of the message):

https://marc.info/?l=newtontalk&m=160547481329308&w=2

 From that message and the very useful photos in the Word document, 
recommended cap replacements are

1) the 100uF, 4V cap to fix the no sound problem (I believe this is 
labelled C1 on the board)

I gotta say, that's a weird looking part - it looks like an aluminum or 
tantalum polymer capacitor, except both leads are on one end of the 
package, not one on either end, and I can't find a polymer cap in that 
configuration.  It might be an electrolytic capacitor in a plastic 
housing to allow it to be more easily surface mounted? I've never even 
heard of that before.

It might be possible to fit a standard aluminum cap in there, but the 
smallest ones I can find are 5mm in diameter, and I don't know the OMP 
well enough to know whether there's that much clearance inside the case. 
If there is, these are some potentials:

https://www.digikey.ca/en/products/detail/panasonic-electronic-components/ECE-A0GKS101/160533 
- the shortest I could find when mounted at a 90° angle

https://www.digikey.ca/en/products/detail/panasonic-electronic-components/ECE-A0GKS101I/2688992 
- slightly longer than the first.

Someone with more electronics expertise here might be able to

2) C51 is 3.3uF, 35V.  From the Frank's photos it looks like he replaced 
the original (which had the same weird case as C1) with a tantalum 
capacitor.  Any of these should work fine then:

https://www.digikey.ca/short/tvb0htrp

There's also a 470uF 10V cap hanging out on the side of the board.  I'd 
replace it on principal, these should be suitable replacements (assuming 
I've guessed the lead spacing correctly):

https://www.digikey.ca/short/bwjdfqpt

I borrowed some of Frank's photos, cropped them, and highlighted the 
target items, you can view them here:

https://immich.chuma.org/s/omp-caps

-V

On 2026-02-06 00:38, Grant Hutchinson wrote:
>> On 4. Feb 2026, at 02:25, Patrick Ketelaar via NewtonTalk <newtontalk at newtontalk.net> wrote:
>>
>> Anyone offer services to replace capacitors in the Sharp Expert Pad PI-7000 or MP100? I have two that are in need and I don’t have the talent/ability.
> On a related note, I would probably be able to perform recap’ing of these devices for North American Newton users, but I would need to know the exact replacement capacitors required and where someone would be able to acquire them easily.
>
> g.
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