Blue Ring Tester Schematic Diagram Exclusive ⟶ 【CERTIFIED】
The ringing signal is AC-coupled via C4 and clamped by D1, D2 to protect the comparator. The LM393 compares the ringing waveform to ground. For a healthy coil, the ringing crosses zero many times. The comparator outputs a series of pulses for each zero-crossing.
A: No. An LC meter measures inductance and capacitance. The Blue Ring Tester measures Q factor and loss—a different parameter. blue ring tester schematic diagram exclusive
Whether you are repairing a vintage arcade monitor, a high-end audio amplifier, or an industrial power supply, this tool will save you hours of guesswork. Build one. Keep it on your bench next to your multimeter. And when a junior technician asks, "How do you know the transformer is bad?" you can smile and say, "I heard its ring." This article is for educational purposes. Always observe safety procedures when working with high-voltage circuits. Flyback transformers and SMPS primaries can store lethal charges even when unplugged. The ringing signal is AC-coupled via C4 and
| Reference | Value | Notes | |-----------|-------|-------| | U1 | NE555 | Timer IC | | U2 | LM393 | Dual comparator (one used) | | D1, D2 | 1N4148 | Fast switching diodes | | D3 | Red LED | Fault indicator | | D4 | Green LED | Pass indicator | | C1 | 100nF | Ceramic disc | | C2 | 10nF | Polyester | | C3 | 100µF / 16V | Electrolytic | | C4 | 10pF | Ceramic (critical) | | R1 | 10kΩ | 1/4W | | R2 | 1kΩ | 1/4W | | R3 | 100Ω | 1/4W | | R4 | 1MΩ | 1/4W | | R5 | 47kΩ | 1/4W | | R6 | 10kΩ | 1/4W | | R7 | 330Ω | 1/4W | | R8 | 220Ω | 1/4W | | RV1 | 10kΩ trimpot | Calibration | | Lx | Coil under test | External connection | | Power | 9V battery (or 9-12V DC) | Regulated recommended | The comparator outputs a series of pulses for
A: Indirectly, yes. If you swap the inductor and capacitor positions, you can test capacitors for high ESR (equivalent series resistance). That's a separate article.
A: The original commercial unit (circa 1990s) had a blue anodized aluminum enclosure and a circular (ring) probe tip. The name stuck.
Enter the Blue Ring Tester. This brilliant, low-cost device uses a pulse ringing test to identify shorted turns instantly. Today, we are providing an along with a component-level explanation of how it works. Exclusive Content Notice: The schematic presented below has been redrawn and refined from original service manuals and reverse-engineered vintage units. It includes component values that are often missing or incorrect in other online sources. Part 1: The Exclusive Blue Ring Tester Schematic Diagram Below is the complete schematic diagram of the classic Blue Ring Tester. This design uses a 555 timer, a comparator (LM393), and a handful of passive components to generate a short ringing pulse and analyze the decay.