Thanks for the suggestion. No I didn't - I'll look it up as I'm not familiar with this. If you know of any online guides for LCD repairs I would be grateful to get a link.
Update - the fourth Ingersoll has also come back to life today! Amazing. Anyway I haven't tried to set them yet as these ingersolls all seem a bit erratic. One resets itself to 12:00 when a button is pressed, on another the display fades away when a particular button is pressed, another is frozen on :00, and the last appears to work well but has missing display segments.
I do wonder if I should revisit the non-working Sandoz now just in case it also does the Lazarus trick, maybe I gave up too soon
This is just a bit of fun really, the watches are pretty damn ugly and I couldn't see them fetching anything on ebay. But it is satisfying for me trying to get them to operate again. And I am definitely learning something from the members here. What a great forum.
J