A company called i4c products makes a great servo isolator that only weighs about one ounce
and is about the same size as your receiver. It lets you run your servos on 6 volts and your receiver
on 4.8 volts (what is was designed for) but the good part is it isolates your receiver from outside
interference from long servo leads etc. The battery for the receiver does not need to be very big
as it uses very little current without the servos.

tommy s