Using non-rechargeable batteries on old HP calculators

[Dieter]

(12-01-2014 08:50 PM)Dave Britten Wrote:  Modern NiMH AAAs probably have comparable capacity to the NiCd AA-size cells that were used when the calculators were originally produced.

They are even better. Around 1980, standard AA NiCds usually had a capacity of about 450 mAh. The mentioned Eneloop NiMHs are rated with typical capacities of 800 mAh (standard type) or even 950 mAh (Eneloop Pro). So you can expect about twice the original operating time.

Standard NiMHs offer even higher capacities – but without the special benefits of the Eneloops: 90% charge after a year or 70% after five years, according to the manufacturer. So even if they sit in a drawer for five years after charging they still should have significantly more capacity than a freshly charged original NiCd pack. ;-)

Dieter