An electronic device can include a motor that rotates a shaft that is coupled to a gear. A belt or a chain can be placed in contract with the gear and other rotational devices. For optimum performance, the chain or chain should be adjusted to an optimum tension. The tension can be adjusted by moving the motor and securing the motor in a position the provided the optimum tension. Alternatively, the motor can be in a fixed rigid position and an idler pulley in contact with the belt or chain can be positioned to provide the optimum tension.