Found my old HP-34C from high school

[Dieter]

(09-22-2014 01:24 PM)Graan Wrote:  So if I understand you right you use 2 separate batteries and attach a metalstrip to connect them?

Yes, I use two standard (button top) Sanyo Eneloop AA cells. Of course these have to be connected somehow. So I grabbed the 34C and looked into the battery compartment. The contacts of the two AA Eneloops are connected with a piece of alumin(i)um foil, folded several times. I also remember having used a thin metal strip, as described. The alumin(i)um foil method has the advantage of being flexible, so even standard button top batteries (with a protruding plus terminal) may be used.

Of course you can also use two (usually flat-top) AA NiMHs, professionally welded together. Which technically may be the better method, as long as it fits inside the battery compartment. But then - how do you charge such a pack externally?

Dieter