isn't that knob just used to display the voltage independently? so after setting voltage of grey body isn't it pointless to adjust the knob when taking the measurement? see 3:51 to 3:59, after turning the knob to the second position, the temperature reading doesn't change(when the knob is still at T3) that implies it is still showing T3... or 2:28 to 3:01 meanwhile notice how just the voltage is reset when the knob is set to the second position? Those stingy guys at tech-ed should have just provided a second voltmeter display(that would't even cost an extra 100 rupees, literally pocket change compared to what these machines go for) instead of making this confusing tin can with one voltmeter and not even providing any manual or user guide or proper specs about the material used for the disc.
