you should check the source to see if it is regulating well check where the optacouple is in that area there is a reference resistance that is associated with the choper transformer which tends to alter and causes the voltage to rise or decrease, check the yoke and The transistor of the horizontal output must be adequate. desolda the leg of the flaybak that is associated with the collector of the transistor of the horzontal output and measures the voltage eb more checks the draiver of the horizontal stage
this reference resistance is associated with the tl 431 the last would be the flaybak if all these parameters are fine there is no where to take
the voltage of the stambay is very low desolda the pin where the flaybakc voltage arrives, disconnects the tsh and measures this voltage well
if you measure in memory the voltage of stambay is either 5 volts or 3.3 volts depending on the model of the TV if you measure it in b more by disconnecting the tsh the voltage is similar to the power voltage of the tv
do the following test disconnect the horizontal output transistor and connect a 100 watt bulb or bulb between the collector and the emitter and you will notice if the bulb is on there is a short if the bulb is turned off you have no short and you can measure the voltage in b more and verify that the flaybak is the problem
Knowing that you have oscillation, you can try the flyback in the circuit. You need a vpp probe, (I send you a diagram). the original is in electronic community but with these values it has given us results.- an external source of 15 / 50vcd.- In this way you can locate if the fault is from the power supply or is a failure of the flyback, yoke or capacitors of tuning (those of the collector) .- If you arm the probe, comment to indicate how it is tested and used. Greetings everyone. Pd.- the probe is not the solution, just a contribution for your measurements. Felipe ascencio
desolda the pin of the flaybak which is connected to the collector of the horizontal outlet, it is where the voltage reaches the flaybak and you will see that the bulb goes out is characteristic that the flaybakc is damaged
friend if the focus gives you the short signal. It can be a diode, the tsh. the source regulator and even the flayback, but if the tsh. It's good, check all the diodes from the source until you go to the horizontal section and even the source regulator may be giving you the short
friend. also check the polyester capacitors that are in series with the tsh. Some can make the short of the tsh.