Should I bother? HP-34C in rough shape

[AndiGer]

Yes, right, the 10 connections on the board.

And as I can see: the inner strip is corroded. The one leading to the 3rd connection on the board. You can bridge it with an additional lead. Look where it is leading to and solder where you already have original solder joints. Soldering the lead at the battery side is not so simple because soldering to the battery contact will not connect very well, but is possible.

Look at this
http://keesvandersanden.nl/calculators/hp33c_inside.php

and this (last picture how Kees did it)
http://keesvandersanden.nl/calculators/h...pair_1.php

Andi
BTW: I am mathematician, have no deeper electronic knowledge