Systems and methods of distributing, dispensing and validating game tickets provide for the use of radio frequency identifiers. The load cup includes an improved substrate edge sensing mechanism to ensure a substrate is present and correctly positioned in the load cup for transfer to a polishing head. In one embodiment, the digital image and the audio description are received from a mobile phone. If the first threshold is exceeded, timing control logic may generate a low band correction pulse to adjust the power converter output voltage, and thereby adjust the error signal to a level within the first threshold. The disclosed method and apparatus are particularly applicable to light assemblies incorporating an array of LEDs.