HP33 Display, contact corosion?

[Mike T.]

If you do get the urge to open the sandwich, mark the positions of the chips before you do, and make a note of the orientation etc. Then just for good measure take a couple of photographs and make sure you use an anti static mat. They will almost certainly try escaping when let loose and being NMOS that will end badly..

I know I killed my first HP33C that way, 'teenix' now has the shell which I expect he is putting to good use but it took me 20+ years to get a replacement!