BTW, even if you have a computer radio, the servo's will work with more power and use less power if you rig the airplane with a couple of things in mind.

Set the radio's end points or throws to be 100%, no more, no less. The radio to servo information is best sent at that setting and that works best with the servo's design.
Now do any changing of throws in the airplane in the rigging. That way, you can control the lever-arms at the servo and at the horn. You can insure the servo has a mechanical advantage or at least has the most favorable disadvantage (3D setups for example).

The computer radios really are kewl and their endpoints and such are very worthwhile, but best saved for fine tuning. The guys who wind up with setting like 140% in the radio aren't getting 140% movement at the surfaces and have dulled the radio's accuracy and reduced the servo's power and resolution and increased the servo's demands on the battery. Sound crazy? It is. And it's true. Nothing of value from doing it and everything less value. So do everything in the airplane that you can.