Using non-rechargeable batteries on old HP calculators

[Nigel (UK)]

(03-26-2018 03:40 AM)John Cadick Wrote:  Waterhosko (on TAS) has been making and selling Battery packs for the classics for a number of years. He makes a variety of rechargeable packs. He also builds alkaline battery packs for the classics. Although he can rebuild OEM battery packs, he doesn’t have to because he makes complete packs that fit perfectly.

Over the years I have bought several of his products (including alkalines) and I highly recommend them. His workmanship is excellent.

A fully charged niCAD is 1.4volts. A fully charged alkaline is 1.55 volts, a difference of less than 10%. I do not believe that is enough difference to cause a problem. Anecdotally, I have used alkalines on all the classics that I own including 35, 45, 80, and 65. It is anecdotal, but I have had no problems.

John

I've used several of the rechargeable packs from Waterhosko as well. They are excellent. Although he doesn't advertise them as suitable for TI calculators, I've found that the three-cell packs fit nicely inside an eviscerated BP-1A battery pack. I use a three-cell NiCd pack in an SR-52 and a three-cell NiMH pack in a TI-58C (the NiMH pack won't quite fit into the SR-52, for some reason). Both fit securely.

Nigel (UK)