NiCAD vs. NiMH Batteries in Woodstocks

[burkhard]

(05-04-2018 12:25 PM)Dieter Wrote:  

(05-04-2018 10:25 AM)rolfmwa Wrote:  Will it be ok to use 1.2 Volt NiMH batteries rather than NiCADs or do I miss something here?

That's why I would generally recommend an intelligent charger for external charging. The Woodstocks' battery holder can be modified so that the two cells can be removed. Among other benefits such a charger (e.g. the BC700) takes care of the batteries and stops charging automatically as soon as the charge is completed. Common charging times are just a few hours.

Actually, even beyond the missing battery scenario: I still won't even use the Woodstock charger myself. Put it in a box with a tag that says "HP Woodstock calculator (25C or whatever) charger Faulty Design -- Do NOT plug into calculator! For historical purposes only". That way, someday your heirs don't blow up your treasure(s) trying to power it (them) with a missing battery.

Failing such measures, within a couple of generations, every one of the bloody things will be smoked.

Considering the poor design of the Woodstock charging circuit, I don't charge any batteries-in calculator. If there's a cell fault, or it gets jostled while on the charger, the calculator is toast.

burkhard