The transistor is the electronic device used in electrical circuitries to strengthening of an initial signal and manufactured of semiconductor materials. The bipolar transistor differs from other types of transistors in what uses as carriers both electrons, and holes.
It is required to you
- tester with the built-in measuring instrument of coefficient of strengthening of transistors, a usual tester in the mode of an ohmmeter or digital check of diodes in the mode and also the special scheme of inclusion in the active mode.
Instruction
1. It is necessary to know that transistors are divided into two types, depending on alternation of layers with different conductivity. To measure the direct resistance of p-n-p (the n-semiconductor with electronic conductivity, p-the semiconductor with hole conductivity) transition, ""minus"" a multimeter connect to base, and ""plus"" in turn to the collector and the emitter. Then measure the return resistance, having given on plus base, and on the emitter and a collector - ""minus"". Check resistance of n-p-n of transition also, but change polarity. The point of these actions is in checking transitions from base to a collector and the emitter, they have to be rung out only in one party.
2. Such check does not give a guarantee that the transistor works regularly, however relying on statistics, you can receive big confidence in its working capacity. Most often at failure of the bipolar transistor there is either a short circuit of conclusions, or a rupture of a chain. If you want to receive absolute confidence, you should check also the transistor in the active mode.
3. For this purpose collect the special scheme, according to the drawing. The scheme is made on the basis of readily available three-output a piezoelement emitter (used in phones). If the transistor is faulty, you will not hear a sound signal. Advantages of this scheme are that it is simple in assembly, with its help it is possible to check the bipolar transistor of any conductivity (having changed polarity of food from a source the SA1 toggle-switch), and at all this you will not be able to damage to the transistor even if you will be mistaken with power supply.