I have a Phantom V1 that I operate with a Futaba 8J transmitter. Using Duracell alkaline batteries in the transmitter causes a voltage drop every five minutes...6.0 volts. 5.9 volts, 5.8 volts, 5.7 volts, etc. The Futaba manual says using 4 cell
Ni-Cd rechargeable batteries (1.2 volts x 4= 4.8...