Pololu 2139 - GWS S125 1/2T 2BB Sail Winch Servo

The GWS Sail Winch servos are commonly used for radio control sail boats, but they are useful for any application where you want easy, inexpensive position control over more than 180°. We carry the 1/2 turn and 1 turn versions, which rotate 180° and 360°, respectively, when provided with the standard 1-2 ms servo pulse range output by many RC receivers. Sending a wider range of control pulses allows the 1/2T servo to achieve approximately 1.5 rotations and the 1T servo to achieve approximately 3 rotations.

These servos do not have physical end stops, so commanding them past their limits will cause them to rotate continuously until you change the commanded position back to something within its actual range. In our tests, this did not damage the servo, but we strongly recommend against it as there is no guarantee this will not damage the servo’s feedback potentiometer.

The sail winch servos feature two ball bearings for improved performance, and they include a specialized servo horn that can be used as a winch. The 27 cm servo cable is terminated with either a female JR connector or a female Futaba connector. The Futaba connector has an extra polarizing tab that can be shaved off to make it compatible with male JR connectors.

GWS S125 2BB sail winch servo with U.S. quarter for size reference.

Included hardware for the GWS S125 2BB sail winch servo (might vary).