A question about alternative power supply for hp41 series

[isanchez]

Hi everybody,

As you all know it was considered to implement a direct power supply connection to HP41 series by mean of the two small golden balls present in early 41c. This was abandoned and the side conector was used to direct feed the rechargable battery pack. The rechargable battery packs are all dead and are not easy to rebuilt.

Despite the golden contacts are present or not, in the keyboard card you can still see the two connection points.
My question is simple: does it work? Are they functional?
If yes, would it be possible to charge four N-size rechargable batteries?, or is it just to power on the calculator?

I was thinking that, if functional, could be useful to design a connector (using 3d printing capabilities and adding the corresponding metal parts) to connect 41 series to a USB port...at least to use 41 on the desk without batteries...

Kind regards
Ignacio