Blue Ring Tester Schematic — Diagram Exclusive

If you build this from a schematic, calibrate it using a known-good flyback transformer. You want the full "Blue" range to light up on a healthy, high-inductance component.

Definitive shorted turn. The component is junk.

The "Exclusive" secret to the Blue Ring Tester’s accuracy lies in the . Because inductors can kick back high voltage, the schematic incorporates high-speed clamping diodes (like the 1N4148) to protect the sensitive comparator inputs without dampening the natural ring of the component. Step-by-Step Testing Procedure blue ring tester schematic diagram exclusive

To get an accurate "Blue" reading, the internal resonance capacitor must be high quality (Polypropylene is best).

Always ensure the equipment under test is powered off and capacitors are discharged. If you build this from a schematic, calibrate

Usually a momentary switch or a transistor-driven pulse that kicks the LC circuit into oscillation.

A series of voltage comparators (or software thresholds) that count how many oscillations exceed a certain voltage level. The component is junk

The circuit is elegant in its simplicity, typically based on a comparator IC like the or a microcontroller like the PIC16F628A . The Core Components