HP-41CV

[rprosperi]

(03-13-2019 06:40 AM)Massimo Gnerucci Wrote:  Spot on, Mark.
Steve, you can refer to this thread to find where the holes are (halfnut vs fullnut).

I agree with Mark and Massimo; try adding a drop of DeOxit Red into the gap around the zero key (try a small amount on all 4 sides) and work the key for at least a minute. Don't press excessively hard, but try to wiggle the key a bit when depressed - the idea is to use the DeOxit to wipe the contact clean under the key. Although DeOxit will generally not harm anything, don't add too much as it is conductive.

Try this technique before opening the case, as it is likely you can solve the zero key problem without risking making the problem worse by stressing and maybe damaging the posts.

Good luck and please report your results.