Got my first electric. G.P. Electrostreak ARF. Bought a Futaba T4EXA radio setup. It came with a R124F receiver and 3 S3108M micro servos. It didn't come with a flight pack battery. Does the onboard Flight battery to power the motor and ESC also power the receiver and servos ? If so, does it step the voltage down from 8.4 volts to the required 4.8 volts for the receiver ? Any help in the problem would be greatly appriciated. I'd like to get this thing in the air and this is the only hang-up .

Smaller ESCs are equipped with a BEC device, a Battery Eliminator Circuit. Should be described in the instructions, but in a nutshell, it regulates the voltage down from the main battery to power the receiver and servos.

There's also another TLA (three-letter acronym) related to ESCs, called the LVC. This Low Voltage Cutoff cuts power to the main motor so it doesn't completely discharge the main battery, leaving you no control at all.