HP-21 - Crazy numbers

[Geoff Quickfall]

As discovered, corrosion and copper sulphate will change internal electrical specs. Vinegar is a great remover of sulphites followed by a good rinse. Of corse after you have removed 5h3 led block and keyboard.

I have soaked a 25 PCA in a glass of vinegar over night without detriment to the circuits.

Also, Electrolytics caps can reform when in use. Others like the button and ceramics a very stable and do not leak or short as the Electrolytics can.

Good job,

Nice to no another ACT Woodstock has survived.