HP 41CL - Power Consumption

[Michael Fehlhammer]

Thank you guys for your answers.

Now we measured power consupmtion in "off" state of
- a version 4 CL with time module: 135 µA
without time module: 124 µA.
- a version 5 CL with time module clone: 390 µA. (!!!)
These numbers are not far away from those listed in the CL user manual.

If I had been aware of the drastic increase in power consumption with the time module clone, I wouldn't have ordered it and would use a classical time module instead.

But I still don't understand what is going on:
The NiMH lady cells are specified to provide 500 mAh.
Divided by 135 µA (or 390 µA, respectively), I would assume a set to last 154 days or five months (53 days or almost two months for V.5/ time module clone).
The actual life cylce is around two weeks only. That is too short by a factor of 4 to 10!

Even if there is some strange behaviour at the end of the discharging cycle which reduces the ideal life span, I can't believe that such effects (alone) are responsible for the observed ridiculous durability.