|
This circuit is designed for testing bipolar junction transistors, both PNP and NPN. Each terminal is connected to a switch that allows us to simulate fault conditions. If both LEDs flash, it means the transistor has failed. If only one of the LEDs flashes, it means the transistor is working properly. A PNP device that is working properly will flash the green LED, while a PNP transistor will flash the yellow LED. If both LEDs are off, it means there is a short circuit between the collector and the emitter. At the top left of the timer, there is a switch that selects the transistor type. Open selects an NPN device, and closed selects a PNP transistor.
|
