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Harald · (This post was last modified: 07-24-2015 10:07 PM by Harald.)

I have just received an HP25 today. The seller had broken it by plugging it in and turning it on with the original battery pack which of course is dead. Luckily nobody had tried to pry out the battery pack that was stuck due to leaking batteries.
To my surprise it looks brand new and seems to have seen hardly any use. Also it is a very early one, serial number is 1510A31263. Does anyone have an even earlier one?
The ACT is probably fried and there is quite a bit of corrosion on the main PCB. The keyboard had very little corrosion though and cleaned up nicely. For now I have replaced the main PCB with one from another calculator, and now the 25 is alive again!
The decimal dots are little triangles rather than rectangles. Is that typical for the early woodstocks? I also have a 21 with such a display.

I'll try and post pictures later.