Abstract: The present disclosure relates to apparatuses and methods to control an electrodeless plasma light source. In various embodiments, an apparatus is provided that includes an electrodeless plasma lamp with a lamp driver circuit. The lamp driver circuit may include a voltage-controlled oscillator to provide radio frequency power to the electrodeless plasma lamp. A radio frequency power detector is coupled to an output of the voltage-controlled oscillator to detect a level of reflected power from the electrodeless plasma lamp. A microprocessor is configured to receive signals from the radio frequency power detector and control a frequency of the voltage-controlled oscillator to minimize the reflected power from the electrodeless plasma lamp.