How to: test a uni junction transistor 2011-07-03

You can easily test the health of a UJT (Uni junction transistor) by using a digital multimeter. Doing these 3 tests will tell you if the UJT is good or bad.

1. Measuring the resistance between B1 and B2 terminals.

Set your digital multimeter in resistance mode. Connect the positive lead of multimeter to the B1 terminal and negative lead to the B2 terminal.The multimeter will show a high resistance ( around 4 to 10K ). Now connect the positive lead to B2 terminal and negative lead to B1...

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