A question about alternative power supply for hp41 series

[Dieter]

(02-25-2016 02:05 PM)wojtek Wrote:  Sorry, I should have been more specific here. I was talking about low discharge accus, like eneloops, which typically have about 1800 mah

Panasonic (or formerly Sanyo) rate their standard AA Eneloops at 2000 mAh typical capacity (1900 mAh minimum).

(02-25-2016 02:05 PM)wojtek Wrote:  Regular nimh accus perhaps can have even 2500mah, according to their makers, but, if you leave for a month or two a fully charged low discharge (with 1800 mah capacity) and a regular accu (with 2500mah), their charge will become the same (because of much bigger discharge feature of regular accu). Later with time every low discharge will win over the regular nimh accu. After three or more months regular nimh will become completely empty but low discharge will still keep more than 80% of its initial charge.

Please don't get me wrong: I am perfectly aware of the many benefits that low-self-discharge batteries like the Eneloops offer. I have recommended them several times in this forum, and I have been using them since they became available about ten years ago. Yes, of course these are the best choice here.

(02-25-2016 02:05 PM)wojtek Wrote:  As for the calculations in the second part of your post, I was talking about 41c in the off state only. I do not know how much juice 41c takes while running, certainly it depends on what 41c is doing.
(...)
I have no data on power consumption of 41c during typical average usage (but would like to know it if anybody knows where to find it.

Maybe these links can help:
Measuring Calculator Current PDF (cf. page 3)
HP41 Info data (search for "battery current")
Some more results in an older post on this forum.

Dieter