HP27 Restoration (Lots of Corrosion)

[Maximilian Hohmann]

Hello!

(04-07-2022 09:24 AM)teenix Wrote:  There could be corrosion inside the holes that mate to the interconnection pins.

These pins are brittle and break easily if stressed.

Yes, I've seen that too (both: the corrosion inside the holes and broken pins). Regarding the green and blue corrosion, outside and inside the holes, I came to the conclusion that the best way to cure it is bathing the PCB in vinegar. The same type that I put on my salad, undiluted. No need to desolder anything, unless broken PCB traces are suspected under the integrated circuits, because the components are not harmed by this rough treatment. Rinse with plenty of water and dry it in a warm place before applying power again.

Regards
Max