A compression-tuned Bragg grating-based laser 800 includes a pair of optical grating elements 802,804 wherein at least one of the grating elements is tunable by a compression device 812,814. The valve tester assembly may include a support, a rotation element mounted on the support for rotating a valve during a rotation event, a control element for controlling aspects of the rotation event of the valve by the rotation element, and an element for detecting a location of the valve tester assembly during the rotation event of the valve. The integrated circuit register can also be reset to reflect the original manufacturer information. The housing is attached to the first surface.