The initial thing to do is have a visual and voltage measurement inside the TV.possible location can be on the Horizontal Circuit Board.you may need to look for Horizontal Output Transistor that is usually mounted on a heatsink.This can be shorted , or have a low supply of applied voltagesfrom the power supply.if the transistor is found good and have a voltage reading of near75 V then assume your flyback transformer is partially shorted.if the voltage will rise of more than 135 V the oscillator may have been block due to over-voltage from the power supply. you might need your soldering skills first to resolder might be hairline cracks on the solder jointsthere would be no component parts ordering till the fault isdetected or voltages have been measured.Although there might be cases that the trouble lies after the flyback secondary output voltages, assuming power supply is good.
you can use the braid wire around the CRT as the reference ground or negative of your multimeter when measuring voltages on these circuits.you can safely discharge the power supply capacitor with a 4.7K 5W resistor to be safe when checking for might be shorted transistor , using resistance scale on your multimeter.if the transistor reads almost or near zero reading assume it is bad.that transistor have 3 pins from the image the collector is the center leg of the transistorthe emitter is the rightmost part, these is where the status of your TV depends.measuring in circuit, you might find that base ( leftmost pin) is shorted to emitter(rightmost) don't worry about it is OK, the important pins are the collector and the emitter. you might need to measure voltages later if the two terminal is not shorted.if it is , have it extracted and double check outside the circuit. only then you can order replacement part of your transistor. you can use the braid wire around the CRT as the reference ground or negative of your multimeter when measuring voltages on these circuits.you can safely discharge the power supply capacitor with a 4.7K 5W resistor to be safe when checking for might be shorted transistor , using resistance scale on your multimeter.if the transistor reads almost or near zero reading assume it is bad.that transistor have 3 pins from the image the collector is the center leg of the transistorthe emitter is the rightmost part, these is where the status of your TV depends.measuring in circuit, you might find that base ( leftmost pin) is shorted to emitter(rightmost) don't worry about it is OK, the important pins are the collector and the emitter. you might need to measure voltages later if the two terminal is not shorted.if it is , have it extracted and double check outside the circuit. only then you can order replacement part of your transistor.
you might also check for other hairline crack on solder joint around these area you might also check for other hairline crack on solder joint around these area
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Answers & Comments
The initial thing to do is have a visual and voltage measurement
inside the TV.
possible location can be on the Horizontal Circuit Board.
you may need to look for Horizontal Output Transistor that is
usually mounted on a heatsink.
This can be shorted , or have a low supply of applied voltages
from the power supply.
if the transistor is found good and have a voltage reading of near
75 V then assume your flyback transformer is partially shorted.
if the voltage will rise of more than 135 V the oscillator may have
been block due to over-voltage from the power supply.
you might need your soldering skills first to resolder might be
hairline cracks on the solder joints
there would be no component parts ordering till the fault is
detected or voltages have been measured.
Although there might be cases that the trouble lies after the
flyback secondary output voltages, assuming power supply is good.
you can use the braid wire around the CRT as the reference ground or negative of your multimeter when measuring voltages on these circuits.
you can safely discharge the power supply capacitor with a 4.7K 5W resistor to be safe
when checking for might be shorted transistor , using resistance scale on your multimeter.
if the transistor reads almost or near zero reading assume it is bad.
that transistor have 3 pins from the image the collector is the center leg of the transistor
the emitter is the rightmost part, these is where the status of your TV depends.
measuring in circuit, you might find that base ( leftmost pin) is shorted to emitter
(rightmost) don't worry about it is OK, the important pins are the collector and the
emitter. you might need to measure voltages later if the two terminal is not shorted.
if it is , have it extracted and double check outside the circuit.
only then you can order replacement part of your transistor.
you might also check for other hairline crack on solder joint around these area