Attach the tester leads across the primary winding of the transformer or the inductor. Read the LEDs:
The tester functions by injecting a low-voltage pulse (typically less than 600mV) into the device under test (DUT). Pulse Injection: A fast pulse creates a magnetic field in the inductor. Resonant Ringing: blue ring tester schematic diagram exclusive
While the is simple, this circuit is very sensitive to stray capacitance. Attach the tester leads across the primary winding