Thanks, again!


I just wanted to post a public thank you to Michael Meyer for reviving my 25C. This is the second one he has fixed for me. The first was a 25 (no C). Both units were non-functional when I bought them and so far Michael is 2 for 2 in breathing new life into them. Both of them were apparently suffering from corrosion to one degree or another. The 25 was in better shape than the 25C. He and I have emailed each other back and forth throughout the process and I will post his comments on the 25C here if he gives me permission. Thanks again, Michael.

J Grim

#3's O.K. to post. Many people in this community have helped me over the last ten years, and I'm just paying it forward.

Happy Programming,


Here is the part of the email Michael sent to me telling me the good news that my 25C lived:

"Well, I have an interesting story for you. There was a good deal of corrosion on the 25C's circuit board, even some on the keyboard traces. I removed some from the board with the dremel brush and put De-oxy solution on it. I reassembled it, resigned to it being non-programmable. The memory chip didn't look to have anything physically wrong with it. I modified and cleaned the battery pack. Then I sat down to write you an e-mail.

While playing with the calculator, trying to program it... suddenly it started showing random keystrokes in program memory. O.K.... that was weird. Then, I could clear out memory and it seemed to take a few keystrokes! O.K.... then, it started working! I didn't want to push my luck with the board as the 25C's are so sensitive, so I didn't want to disassemble it again. But, then it started to malfunction again. So, I decided to take the chance and took it apart and re-soldered the memory chip and the ROM chip.

OMG... you have a fully programmable, fully functional 25C. Here's my conjecture: The Deoxy solution had some time to improve conduction somewhere just enough to make it work intermittently enough to alert me to it's possible survival.

I plan to play with it a little more while I clean the front with the usual Armor-all scrub. Looks as if I'm 2 for 2 for bringing these to life. Good feeling for a doctor."

A good story. Hopefully, it helps other people to fix those dead calculators that are out there on the "parts piles"

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