Introduction Various offi ce automation (OA) devices are used in the offi ce, including scanners, printers and fax machines. The stepper motor is essential in the operation of such equipment. The downside of having the stepper motor, however, is the humming generated during its operation, which ultimately contributes to environmental noise in the offi ce. For this reason, the manufacturer of the stepper motor needs to evaluate and identify the magnitude of vibration. This is necessary for product improvement as well as market acceptance and recognition. This application note describes the measurement of the stepper motor vibration noise using the Agilent USB DAQ.