[34S] battery warning indicator / question

[John Galt]

Thank you Matthias!

For those interested, I have found wide differences in performance from various battery manufacturers. For example. The Panasonic batteries I had originally been using perform poorly under load, when weak. By that I mean their voltage drops precipitously when current exceeds a certain value (which I have not yet determined). On the other hand Maxell battery voltage appear to decrease in a more linear fashion under load, when they become weak.

Using BATT (to be sure, a crude means of determining what's going on) and using a program loop storing its value in memory until the calculator shuts down yields voltages of 2.6 or 2.7 with the Panasonic batteries. Maxells consistently record 2.5, and the battery icon gives much more warning when they're about to fail.

Admittedly this is a very unscientific test, but the problem I was complaining about is going to be very heavily influenced by the type of batteries one uses.

Limiting current is a very good idea, and it seems easily accomplished.

Ideally, a WP 34S would benefit from a power supply better than what the 30b hardware offers us.