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Re: T.V. wont turn on
The voltage might be low because is being loaded down,open the collector of the output transistor and measure the voltage again,if it goes up to 130 or the voltage is suppose to have you might be looking at a bad output transformer(flyback)there are other parts that can cause the loaded down voltage,the yoke can be one and capacitors in the deflection circuit,check to see if one of this caps is overheated (bubble)or cook,Be carefull if you open the collector when you measure the voltage,If you can try measuring the voltage somewhere else.Lets Us know if you need meore help.
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You're either losing high voltage or power supply is not producing the horizontal drive signal, Check for 130v on the collector of the horizontal output transistor, if you're missing your voltage, you have a power supply problem. If voltage is too high you have something open in the power supply such as a low value resistor. If its low, something is shorted in power supply, possibly voltage regulator ic.
look for trouble in the low voltage and or high voltage power supply circuits. the popping sound could be an exploded safety capacitor in the horizontal output to the flyback transformer. the horizontal output transistor maybe damaged. chances are the low voltage regulator is also damaged.
I disagree with given info, this tv has no horizontal output transistor because it is dlp tv. 3 red light blink means lamp cover is not placed back properly after lamp replacement/ lamp checking. Make sure lamp cover is fixed back in its place securely and tight.
I suggest you look at the Horizontal output transistor, when it goes short the supply is in protection mode, it is pointless reading voltages at this stage, check the transistor located close to the Horizontal output (Flyback) transformer and normally mounted on a large heatsink. Check the caps in the primary power supply stage....hope that helps..Phil
Check all fuses in the power supply and look for any bad connrctions on the PCB. You are probably missing the 130 volt supply to the horizontal circuit. Common reasons are: Shorted horiz output transistor; flyback transformer, picture tube arcing , bad power regulator IC. In short, you need to get a qualified tech for this symptom. Hope this helps.
If the output transistor is good you need to measure the voltage at the collector to see if it has the needed voltage to operate,is also important to check the conections in the horizontal driver transformer and also measure the volts at the collector of the horizontal driver transistor,before you check any voltages check for loose conections and overheated areas,after everything is nice and solid then you can check for volts,be careful while measuring voltages and try not to touch anything with your bare hands while the set is on.Let us know how it goes or if you need more information.
This is like a car running without a driver,the horizonatl output transistor has the voltage it needs but it does not have horizontal drive signal applied to the base of the horizonatl driver transistor,the driver transistor should have a signal coming from the signal processor where the signal is generated just to get give it to the driver this driver then it gives it to the output to energize the flyback and light up the picture tube and generate a few other supplies,158 volts are there because the output is not turn on,try measuring voltage somewere else in the set and not at the collector of the output,there is a b+supply that goes to the signal processor(8 to 12 volts),check to see if you have this voltage,I couldn't tell you the pins in the siganl processor IC without squematic,It seems you know your way around tv service but be careful when checking voltages.Let Us know if you need more information.