The identification of several poles of the transistor

If the circuit diagram, look directly at the following picture:

Note: b is the base, C is the collector, E is the emitter

If the specific components, the method is as follows:

I, judging the transistor base

For the NPN transistor, with a black Watch pen to connect an electrode, the red pen is connected to the other two electrodes, if the measurement results of a small resistance, the exchange of the pen after the measurement results are larger, you can determine the first measurement of the black pen is connected to the very base pole; if the measurement results of a large and small, In the first measurement, the black form is not the base pole, and the other electrodes should be re-measured.

II. Judging transistor emitter E and collector C

After the transistor base is determined, by exchanging the pen two times the resistance between the E, C poles, if the results of two measurements should be unequal, then the measured resistance value of the lower one for the red table is the e-pole, the Black Watch pen is the C pole.

For PnP-type transistors, the method is similar to the NPN tube, except that the red and Black Pens Act in the opposite direction.

When measuring the resistance between E and C poles, it is important to note that the transistor's V (BR) CEO is so small that it is easy to penetrate the transmit knot.

III. Judging the transistor pole type

If you know the base of a transistor, you can use a red pen to connect the base, the black pen to touch the other two poles, if the measured resistance is large, then the transistor is an NPN transistor, if the measured resistance is small, then the transistor is PNP-type transistor.
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