Fixing a HP34C

[BobVA]

(07-13-2023 12:24 AM)agarza Wrote:  

(07-12-2023 11:52 PM)teenix Wrote:  I have seen examples where the parts have been soldered to the film layer, but you would have to be careful not to overheat it.

I was thinking of soldering the components directly "a la surface mount". Do you have any photos of someone that has done that?

I had a 34C that went from intermittent to completely dead over the course of a few months. Disassembly and cleaning didn't help.

As a last ditch effort I soldered all the components to the board, and it's been working for a year (with light use).

I worked *very* quickly, using lead-based solder, and still wound up melting a couple of traces through the board (fixed with bodge wires). I tripled checked part identification / orientation and was extremely careful to avoid making any solder bridges. Rework would be very difficult - it's like working on a circuit board made out of chocolate.