Which batteries for 41CV?

[Garth Wilson]

(10-16-2018 07:20 PM)HP67 Wrote:  Thanks. Ok, looks affordable on TAS. How long does a set last in a 41CV used for an hour or two a day desk duty and programming? Ballpark number just to give me a general idea would be appreciated. Thank you!

I originally got my 41cx in 1986 for controlling equipment on the workbench at work through HPIL and the HP82169A HPIL-to-IEEE488 interface converter. It actually ran an automated test setup for production for the first year or so, getting used many hours each day, and a set of alkaline batteries lasted a couple of months IIRC. I suspect the calculator is basically idling when it's waiting for readings to come back from the equipment. After the control was transferred to a 68000-based HP9000-series computer, I kept using the HP-41cx daily, but not constantly, and a set of batteries lasted a couple of years. After eBay came into being, I got a double extended memory module, and battery life dropped to six months. A year ago I got a Clonix-D module and put several ROM module images in it, and battery life now is down to ten weeks. I get 20 N cells at a time on eBay for $0.85 each, including shipping, which is a lot cheaper than Radio Shack used to be!