okay guys this is going to be my shortest video that I've ever made you're never gonna find one shorter than this least not from me one of my viewers was asking about measuring transistors I'm just going to show you how to measure a transistor this is a bipolar transistor on a transistor you've got three leads an emitter base and collector important thing to remember about bipolar transistor is essentially it's two diodes both from the collector to the base and the emitter to the base so when you want to measure an NPN transistor for example put your tester into diode test mode put your this is an NPN so the base is positive put your positive terminal on the base measure between the collector and the emitter and the base so positive terminal on the base the biasing of this is base collector emitter so between collector and base you'll see this about 0.5 volt drop for a silicon transistor between the base and the emitter I gain about 0.5 full drop this is a good transistor if I reverse the leads it will be open everything else is open so open between the base centimeter and the base and the collector and of course we also have to measure between the emitter and the collector and that'll also be open if you have any conduction between the collector and the emitter such as the short that's bad okay if you get a beef or you get any reading between your emitter and your collector your transistor has failed if you have any reverse bias between the base and the emitter and the collector in the emitter the transistor is bad this would be a PNP transistor it'll be the opposite your negative would go on the base if you don't have a diode test function on your meter you can still measure it with the ohms test function on your meter a gain same thing you will measure some resistance in this case it's about megohms between the base and the emitter and the base and the collector about three mega ohms same thing in the reverse direction it's open you see that and it's open whoops touching the base there and it's open there as well and if I put my negative on the base this being an NPN transistor again it measures open so you could measure it with an ohm meter or more preferably the diode test function because then you're actually testing the voltage drop across the junction this works with bipolar transistors only this type of test does not work with MOSFETs you can test MOSFETs as well but the readings are going to be different it's also going to be different if there are any internal resistors some transistors actually have internal bias resistors in them and then you will get a reading but it all detect it all depends on the type of transistor but this test is for bipolar transistors only hope it helps