Written by: Newton C. Braga

 

Procedure

The figure shows how to use the multimeter in the indicated tests.

 

 


 

 

 

For a silicon NPN transistor we have the following possible measures:

a) Emitter voltage between 0 V and some Volts

b) Base voltage - approximately 0.6 V above the measured voltage at the emitter. For germanium transistors approximately above 0.2 V.

c) Collector voltage - greater than the base voltage up to the value of the supply voltage if the collector charge is of low impedance.

 

Abnormalities:

a) Base voltage equals to the emitter - short transistor

b) Zero Voltage - Transistor Open or Short

c) Collector voltage nil or equals to the emitter - short transistor

d) Collector voltage equals to the supply with load that is not of very low resistance - open transistor.