Hi Guys

In the old days, who can remember, 4 dry cells were used in the reciever - this gave a total of 6 volts to receiver and servos. 5 x 1.2 volt= 6 volts so there should be no problem as long as its nicad or NiMh(1.2 volt per cell).

Poly cells are different and will definitely require a regulator.

I have used 6 volt 5 cell packs for the last 8 years on DF, Large Scale and Turbines and have had no problems.