Ring Tester Schematic Diagram Exclusive — Blue
The decaying AC ringing waveform is fed into a high-speed voltage comparator (like the or an internal microcontroller comparator).
: House the circuit in a small plastic project box. Use short, high-quality silicone test leads with heavy-duty alligator clips. Long or coiled test leads add stray inductance, distorting the ring test. How to Interpret the Results
: The tester uses pulses of approximately 600mV or less, allowing for many in-circuit tests without damaging sensitive semiconductor junctions.
+9V to +12V DC Input │ [ ] R1 (10k) │ ├───●───────┐ │ │ │ [ ] [ ] [ ] R4 (47k) R2 [ ] [ ] R3 [ ] (10k) │ │(10k) │ LM3914 LED Driver │ │ │ ┌─────────────────┐ Pulse Input ●───┼───────┼───►│ Pin 5 (Signal) │ (From MCU/555) │ │ │ │ │ │ [ ] [ ] === │ Pin 1 -> LED 1 │ [ ] R5 [ ] [ ] C2 │ Pin 10 -> LED 10│ [ ] (1k) │ │ (1nF) └────────┬────────┘ │ │ │ │ │ ●────────┴─●────────● │ │ │ │ │ │ │ │ │ │ ===== C1 ├─┐ │ │ │ [ ] R6 (10nF) │ └─┼────────┘ │ [ ] (22k) │ │ │ │ │ │ LM393│ │ │ ●──────────┴─►(Inv) ├───┘ │ │ (Non) │ │ [─] Test ▲ │ │ [─] Probes └────┘ │ │ │ └──────────────────────────────────────────────┴─── GND Components List IC1: LM393 (Low Power Dual Voltage Comparator) IC2: LM3914 (Dot/Bar Display Driver) Resistors: R1, R2, R3: 10kΩ (Metal Film, 1/4W) R4: 47kΩ (1/4W) R5: 1kΩ (1/4W) R6: 22kΩ (1/4W) Capacitors: blue ring tester schematic diagram exclusive
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The Blue Ring Tester is a diagnostic tool for identifying short-circuited turns in high-Q inductive components, largely based on Bob Parker's original Dick Smith Electronics K-7205 design. An updated version, which features specific schematic details like the CD4015BE shift register and optimized R7 resistance, is currently manufactured by Anatek. Detailed schematics are available in the Blue Ring Tester Assembly & User Manual Flippers.com AI responses may include mistakes. Learn more Anatek Blue Ring Tester Assembly and Review HD
: Keep the traces between the test input terminals, the The decaying AC ringing waveform is fed into
For your safety and legal protection, I cannot produce or share an exclusive schematic. If you’re looking to build one, I strongly recommend studying known hobbyist designs that include proper safety warnings and isolation. Always assume lethal voltages may be present.
: Keep the traces between the test leads, the protection diodes, and the 10nF tuning capacitor as short and thick as possible. Stray inductance or resistance in these traces can artificially lower the "Q" reading.
Did you build this exclusive version of the Blue Ring Tester? Share your PCB layouts and calibration experiences in the comments below. Have an exclusive mod? The community is waiting. Long or coiled test leads add stray inductance,
: Indicate a healthy component with many rings.
: Arranged to show the Q factor—more lit LEDs represent a higher Q. Red (1-3) : Indicates "Bad" or Low Q. Yellow (4-5) : Indicates "Marginal" or Medium Q. Green (6-8) : Indicates "Good" or High Q.
