The present invention relates to a light-emitting device comprising a substrate, a circuitry, a LED in electrical connection with said circuitry, and a heat sink arranged to transport heat away from the LED, wherein the LED is in thermal contact with said heat sink through an opening in said substrate. The clock signal generator includes a synchronizing circuit for generating an output clock signal from an input clock signal and further includes a delay circuit having an input coupled to the output of the synchronizing circuit. One or more of the mixer elements and ejector shrouds comprise a mixerejector pump which increases the energy extraction potential of the turbine system. A DUT detector samples the DUT response signal generating sampled DUT data using a sampling period that is shorter than a shortest time between timing signal triggers.