The Parallax feedback 360° high speed servo is a combination of a standard servo, continuous rotation servo, high-speed servo, and encoder in a standard servo package!
These servos are the holy grail for projects that require positional feedback combined with the flexibility of operating in either standard or continuous rotation modes. Like most continuous rotation servos, the Feedback 360° is controlled by a 50 Hz pulse-width-modulation signal. What sets it apart is a return signal line from an internal Hall effect sensor system that provides digital angular position feedback.
Utilizing this feedback signal, your application can make the servo to turn to and hold any angle, much like a standard servo but with an unlimited range of motion. Or, rotate the servo continuously at a controlled, verifiable speed — up to 120 RPM — as a robot drive motor. Control signal response is nicely linear across the speed control range.