hi

most rc receivers reduce the voltabe from the battery pack thru a voltage regulator to about 3.2 volts, so I have read. however I usually quit flying when and it my airborne pack reaches around 4.4 volts<4 cell pack>, about 1.1 volt per cell. the battery manufacturers usually recommend you not take a nicad below 1.1 volt per cell due to dangers of reverse polarity. how critical?...don't really know.

good luck and happy flying

pt19 flyer