How to customize a servo?

[BrianG]

It's all about the signal pulsewidth and feedback pot in the servo itself. Servos generally have something between 90* and 180* rotation because that is the range for most potentiometers. You could get multi-rotation by using a multi-turn pot. However, the way you want the servo to operate will have some difficulties.

A servo will travel to an absolute position set by the pulsewidth, not by a relative position. So, your radio would have to have a switch with 10 positions (two clicks X 5 times). The steering and throttle are continually variable, but ch3 is usually 2 position, or at most, 3 position. If you didn't need a steering or throttle control, you could replace the pot for that control with a rotary switch that had resistor values soldered on that would give you the steps you want.