Worm Gearmotor + Hall Sensor Encoder, Ratio 1650:1. Output Shaft: 6mm Dia. Output speed at nominal 12V: 3rpm.
The rear of the motor is equipped with a dual channel Hall effect quadrature encoder with outputs A and B. The phase difference between the channels is 90 degrees. A single circuit cycle equals 12PPR of the motor. To calculate the pulses per revolution of the output shaft of the gearbox for a single channel you would multiply the gear ratio by 12. For maximum resolution, counting both the leading and trailing edges of the pulses on both channels A and B of the encoder will quadruple the number of pulses per revolution, so in this case you would multiply the gear ratio by 48 to calculate the pulses per revolution of the output shaft.