im having trouble testing a mosfet. its an n channel STP7NK80Z diode protected. i have been trying to learn how to do the simple test with a multimeter set on diode test. as i understand it i put the positive lead to the drain and the negative lead to the source. i should get no reading.now if i touch the drain and gate together it should let the mosfet conduct. if i measure with the red lead on the source and the black on the drain i get a reading which i believe is the reading of the protection zener diode. am i doing this right as i have tried 2 mosfets now and cant get them to conduct. is there something different with this being a diode protected one??