An electrodeless fluorescent light source has an electrodeless lamp mounted in a termination fixture which includes an inner conductor and an outer conductor disposed around the inner conductor and is coupled to a high frequency power source. Power is coupled to an ultraviolet-producing low pressure discharge in the electrodeless lamp which acts as a termination load within the termination fixture. A phosphor coating on the inner surface of the electrodeless lamp emits visible light upon excitation by ultraviolet radiation. Alternatively, the phosphor coating can be on the inner surface of a transparent envelope which forms part of the termination fixture. In this case, the phosphor coated envelope can be removable from the light source. The light source can be dimmed by reducing the microwave power input. Frequency of operation is typically from 902 MHz to 928 MHz.