I found the firmware files on this site and down-graded to 3.8.1.6, connected the Pronto to a stabilised variable power supply and started reducing the voltage 0.1V at a time.....
5.4V 4 bars 5.3V 3 bars 5.0V 2 bars 4.8V 1 bar 4.6V LOW 4.0V switch off
Increasing the voltage in 0.1V steps the result was similar but 0.1V higher for each step which seems about right to give some hysterisis.
I then up-graded to 3.8.1.7 again and the results were exactly the same.
Does anyone know what the voltage / bar relationship should be ?....and is there any way of changing it.
Seems like powering with Ni-mH / Ni-cd is running pretty close to the wire to me as 4 cells would give 5.6V max dropping to 4.4V min (1.4 to 1.1 V per cell)
Also, what is the highest voltage these will safely run at......with 5 x Ni-mH the fully charged voltage is 5 x 1.4 = 7V........In theory 4 fresh Alkaline batteries would give 4 x 1.6 = 6.4V.....I don't want to risk blowing it up as they don't seem to be available any more !!!
