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.
