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The successor to the famous Bob Parker FBT/LOPT kit and companion to the.

The successor to the famous Bob Parker FBT/LOPT kit and companion to the. The Blue Ring Tester for FBT/LOPTs and all Hi-Q inductive components

What our customers say:

I'll tell you why I DO feel lucky, and that's having purchased from someone who still understands the meaning of customer service! That goes a long way in my book (well, if I had a book). - Tod

Thank you very much for the Blue ESR and Blue RT kits. They worked out very well and I can honestly highly recommend your kits. I am very impressed with the quality of your kits and the detail that you provided to make the assembly absolutely painless. - George

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Blue Ring Tester kit (battery not included) $42.00

Fully assembled, tested and aligned including 9 volt battery $65.00

Easy access battery compartment.

The easiest assembly ever. All components are on the solder masked pc board.

This ring tester is an inexpensive and effective way to test any high Q inductive component. It is especially useful for doing a quick check on flyback transformers, line output transformers and other high frequency inductive components like deflection yoke windings and SMPS transformers.

Hi Q = low loss inductive components. A shorted turn or coil will show no rings. A shorted FBT diode will show few or no rings.

The LEDs on the left side show the Q of the device being tested, more lights = higher Q, i. e., no lights = short circuit, red = Bad or low Q, yellow = ??? or medium Q, green = Good or high Q.

Tests in circuit, & test leads are non-polarized
Easy-to-read, high brightness red, yellow and green LEDs display the Q of the device being tested.
Simple operation for fast easy diagnosis of faulty inductive components.
New Improved design increases sensitivity for low impedance components such as SMPS transformers and deflection yokes.
Includes a ferrite core and mag

Download the The manual includes a description of how ring testers work.

Tools needed:

  • Solder iron with small tip (40 - 60 watts is ideal)
  • Rosin core solder
  • needle nose pliers
  • wire stripper
  • wire cutters - small diagonal cutter is ideal
  • #1 phillips screwdriver

Assembly time will be 1 to 1.5 hours with average soldering skill.