Can a user measure voltage with the 41-C series?

[4ster]

On the HP-41, does it have an internal voltmeter that triggers the BAT symbol at a set voltage? Or is it simpler than that?

I have been wondering if there was a way to access the internal meter to display the battery voltage before the BAT annunciator appears. I don't recall reading about this years ago when my calculator was new, and I am not spotting anything now as I am reading archived material.

It would be useful to have access to a "fuel gauge" of sorts. I have started running NiMh batteries and expect that the "5-15 day" life mentioned in the manual is a lot shorter with NiMh. I keep a fresh set of spare alkalines with the calculator in case the BAT annunciator appears. I'm not ready to trust to a second set of NiMH for backup.