About Blue Ring Tester
Since after i sent out the March Repair Newsletter i got quite a number of response about this meter. Some already bought it and for your information this meter is not design to measure the secondary winding of Flyback transformer or even the SMPS transformer due to generally the secondary windings have less inductance. This meter is use to check the Primary winding of Flyback transformer, Primary winding of SMPS transformer and also for any coils that have inductance of more then .3 milihenry. The higher the inductance of a winding the higher the LEDs of the Blue Ring Tester will lit. Lets put this ina neasy reference. If you see a coil with many turns then generally this meter can test it. If you see a small coil with less winding in it then expect the meter to show either one LED or no light at all.
If you can’t see the winding, you can always compare with another good equipment coil and see the result. If you can’t see the winding and do not have any equipment for comparison then you have to use inductance meter to check for the value and make sure it has more than .3 milihenry.
If you do not have inductance meter then i guess you just have to roughly guess the inductance (by looking at the physical size of the coil) and expect some result. If the LED is fully lit you are now sure the coil has no shorted turns. If the coil had caused the meter LED to goes off then suspect it may have a severe shorted turn but again it still come back to your experience whether wants to replace it or not.