I would like to set up a circuit to test Flyback and yoke

Monday, May 21 2018

1 I would like to set up a circuit to test Flyback and yoke Often the defect of a TV is in the high voltage transformer (flyback). I would like to build an efficient circuit to test the flyback, know if it is in perfect order or not. 5 Re: I would like to set up a circuit to test Flyback and yoke If you are referring to the flyback testing in the context of repairing a TV, there are well-documented and secure procedures in the TV schematics, most of which are based on the visualization of characteristic waveforms at specific points in the circuit. A standalone test by handling outside the equipment is intrinsicly risky and inadvisable. When flyback get burned the whole deflection circuitry (ie, high voltage stages) becomes inoperative and you see nothing in the screen, so if if you are lucky the rest of the circuit (ie, sound) keep working and you can determine the problem w/o even having to open the TV. BTW, I'm moving this thread to the "Repair Tips" section, but I'm particularly confused whether this question should even be moved to the "Tubes and Retro" section; nowardays it is rare to see any issue regarding to this subject. Re: I would like to set up a circuit to test Flyback and yoke Hello jfminformatica, The best way to determine if a flyback xformer or deflection yoke are faulty, is with a shorted turns tester. Most flyback's end up with shorted turns in one or more windngs (this is the most common fault). Some will burn internally and form a c.r.a.c.k on the outer casing. Some will have defective focus and screen pots (rare). As for deflection yokes, they are mostly reliable and rarely fail. Most failures are due to corrosive glue applied at the factory that eventually eat some of the windings. But shorted turns within can also occur, but as I've said, rarely. The only reason you need to check for shorted turns is mainly due to the set hiccuping or it continuously destroys the horizontal output transistor. If you are finding that the set hiccups, just place a jumper wire between the base and emitter of the horizontal output transistor. If it continues to hiccup, then the flyback has shorted turns. If the hiccuping stops, then there's something else wrong, perhaps in the horizontal or power supply stage/s. You can build your own shorted turns tester, but you'd need to purchase a copy of one of Silicon Chip magazines issues, found below: