Voyager battery lifetime

[Hans-Peter]

I inherited an HP12c from my father who died 20 years ago. Now I had to change the battery and it had a label inside the lid with my father's last battery change March '91. I've used the calculator from time to time, most recently about half a year ago. It only had three slight traces of corrosion on the contacts, which I was able to wipe away with a brush. The batteries were Energeizers. That's different from the power-hungry HP35s.

Hans-Peter

[damaltor]

Yeah, the voyagers batteries usually last pretty much forever. depending on the type of batteries it is to be noted that the asterisk indicator might come up a few hours or just a few minutes before the end of life of the batteries.

[GreyUser]

The original design Voyager processor standby current is so low, it basically comes down to cell chemistry lifetime.

Silver oxide 303/353 cells will live significantly longer in the application than regular alkaline cells and twenty plus year life with said batteries and intermittent use is common.

[Steve Simpkin]

"HP began designing a new CPU called Saturn and series of calculators to follow the HP-41C but these designs became quite complex so they designed another series of midrange calculators based on improved HP-41C technology as a short-term measure."

Although the HP-11C and HP12C members of the HP Voyager family were formally introduced for sale in 1981, the earliest production examples of these two models were manufactured in late 1980. Thus the HP-12C has been in continuous production for over 41 years. The internal hardware has changed over the decades but the HP-12C you can purchase new today has the exact same functionality as the one introduced in 1981 and is running the same 41year old core firmware code (via emulation). Not bad for a "short-term" product.

I just recently changed the 3 silver oxide batteries on my 1987 HP-12C. I suspect I will no longer be on this Earth when they need to be changed again.

https://www.hpmuseum.org/tech10.htm