A self-propelled lawn mower including at least one cutting blade and at least first and second rear drive wheels. In one embodiment, a first and second defect is formed to partially expose the inner tension layer. The control valve controls the flow of fluid between the first and second fluid chambers. The adjusted reference signal is delivered to an oscillator such that the oscillator begins oscillating at approximately the same frequency as the reference clock signal to provide a fast locking synchronization device. The automatic remote firmware update mechanism can form a part of firmware installed in the imaging system.