How can an analog meter be used to test a diode?

An analog meter can effectively test a diode by measuring its resistance in both forward and reverse bias configurations. When conducting this test, the ideal behavior of a diode is demonstrated by how it responds to these two scenarios.

In the forward bias direction, a properly functioning diode will exhibit low resistance, which indicates that current can flow through it. This is because the diode is designed to allow current to pass when forward-biased, showing a typical behavior of a semiconductor device.

In contrast, when the diode is reverse-biased, it should show high resistance, indicating that current does not flow through the diode, which is the expected behavior in this condition. This high resistance essentially indicates that the diode is blocking current, confirming its integrity.

Testing resistance in both conditions enables the technician to effectively discern whether the diode is functioning correctly by evaluating its response to different biases. This method leverages the specific characteristics of diodes and is a straightforward approach when using an analog meter.