Should I bother? HP-34C in rough shape

[Geoff Quickfall]

The battery problems are affected by two things, both not necessarily HPs fault.

1. Battery size; width and length have increased by the manufacturers to augment battery life. This increase is now at the maximum dimensions (can't remember the agency in charge) and stresses the battery tabs on the 30 series. The original size were no problem. I lightly 'tap' the cathode nipple to shrink the length of the battery by a silly mm or two.
2. Owners that leave batteries in the calculators, watches, flashlights, palm pilots... are idiots.
3. opening the case by amateurs leads to cracked cases at the base of the calculator. The techs at HP were skilled at separating the shell.
   

The 34c was the first intro of the solver and had a nice size RAM for programs and were continuous memory. The display was larger and included 1000 radix and which was selectable between dot and comma. The keyboard snap is probably the best of all HP's. The down side were the first heavier variants with the floating ICs. At least you could swap ICs at the repair depot but over time the compression foam does not return, ie. press the keys into the PCA. Easily repaired by soldering them in place. The other nice thing from a repair point of view was the ability to swap ICs and LED block without desoldering. The second version, lighter had the ICs soldered.

Main problem about battery compartment size with newer oversized batteries are, as Max alluded to when he faults HP:

1. Broken battery tabs due to battery manufacturers increasing battery length and the low tolerance to accept these batteries.
2. Battery leakage due to neglectful owners which migrates into the calculator along the flex ribbon to the main PCA.
   

Battery tabs can be replaced but require you to be handy. The flex ribbon can be removed and the three traces can be hard wired to the PCA solving the flex ribbon problem.

So although they spice series seem problematic I would not blame HP. I like the 34c due to its memory, LEDs, size and key snap feel.

Geoff