DT830B Transistor Test

The DT830B digital meter can test a transistor by measuring its hFE value and displaying it. The user then has to compare that value with that stated in the datasheet to determine if the transistor is operating within normal parameters. In order to do this, insert the transistor correctly into the test socket as shown in the photograph, and set the range switch to hFE position.

Find Transistor Parameters

For example, if you want to test a BC549C general-purpose transistor, you must first find the datasheet and look-up some basic parameters.

1. Locate the emitter, base, and collector terminals.
2. Determine whether the transistor is a PNP, or NPN type.
3. Find the stated hFE value from the datasheet.

hFE Parameter

It is always a good idea to get a meter that can test a transistor. There are many models with this function worth seeing and getting. Many of them simply display "good" or "bad".

I am always interested in seeing the different ways in which a meter can display the test readings. However, this one simply displays the hFE parameter, which is good enough.

Inserting the Transistor

Insert the transistor in the testing socket. The meter readout will be the hFE value of the transistor when the base current is 10 µA and Vce = 2.8 V. For this transistor, an hFE value of around 500 indicates that the transistor is operating correctly.

Another way of testing the transistor is using the diode test function and checking each junction. I have a page that shows how to test a typical bipolar transistor of an amplifier using the diode test.

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