Hi,
I try to fix a HP 33C, which doesn't do anything when I turn it on. So my first guess was, that it might be a contact problem. I managed to open the case - it is one of the older models, which has metal retainers inside and where the spine holds the chips in place (like the left one in http://www.hpmuseum.org/30comp.jpg ).
I don't want to dissamble the calculator completely, so my question is: does anybody know if the minus pole of the battery has to have contact with any part of the circuit board you can access easily (i.e. through the "windows" of the plastic cover)? The positive pole has contact (on/off switch in off position) with the first three little contacts (from the left) in the left window, but I can't find any point the negative pole has contact to.
Thanks in advance, Frank.