Not really sure. The tv came like that. There's no heat though. Now the tv had good picture and sound. Except the buzzing sound from the back light transformer.
Please put the pin name on each pin of that LED connector, your picture is not showing the pin names.
LED 4K - Silver - 5.50v
LED 4A - Black - 69.6v
LED LED3K - Silver - 69.6v
LED 3A - White - 133.7v
LED 2K - Silver - 5.66v
LED 2A - Blue - 69.7v
LED 1K - Silver - 69.7v
LED 1A - Red - 134v
T501 is the power transfomer that supplies 12V, 24V, and VLED power supply that feed the two LED boost converter power supplies to drive the LED strings.
So disconnect the LED connector and see if the buzzing stops.
T501 is the power transfomer that supplies 12V, 24V, and VLED power supply that feed the two LED boost converter power supplies to drive the LED strings.
So disconnect the LED connector and see if the buzzing stops.
when the tv is only on no signal mode, buzzing is lower, but if i put a picture or movie on, it becomes louder. I disconnected the backlight cable, no buzzing sound. I can see still image on the screen if i put a torchlight.
when the tv is only on no signal mode, buzzing is lower, but if i put a picture or movie on, it becomes louder. I disconnected the backlight cable, no buzzing sound.
Put the LED connector back in place, then lower the Backlights level (not brightness) to about 30% to see if the buzz gets lower.
Put the LED connector back in place, then lower the Backlights level (not brightness) to about 30% to see if the buzz gets lower.
Ok the thing is, this tv doesnt have a backlight adjustment, it only has 3 modes, standard, power, best picture. So i assumed best picture is high and i selected it, buzzing a bit louder, then i put standard or power mode, buzzing goes lower. Then i started playing with contrast, when goes to 30% it buzz louder, goes to 50% not loud, below 30% louder. When playing a video, buzzing is lower. I think the buzzing gets louder when image becomes more brighter
Ok the thing is, this tv doesnt have a backlight adjustment, it only has 3 modes, standard, power, best picture. So i assumed best picture is high and i selected it, buzzing a bit louder, then i put standard or power mode, buzzing goes lower. Then i started playing with contrast, when goes to 30% it buzz louder, goes to 50% not loud, below 30% louder. When playing a video, buzzing is lower. I think the buzzing gets louder when image becomes more brighter
Contrast is for Video adjustment, it does not affect backlights level or backlight circuit.
Are you sure the buzz is not coming from speakers?
Try adjusting brightness, this TV may be using brightness for the backlights level adjustment.
Also try turning off 'DYNAMIC BACKLIGTS' mode, see page 36 of user manual: https://cdn.badcaps-static.com/pdfs/...45d25a9b6a.pdf
Contrast is for Video adjustment, it does not affect backlights level or backlight circuit.
Are you sure the buzz is not coming from speakers?
Try adjusting brightness, this TV may be using brightness for the backlights level adjustment.
Also try turning off 'DYNAMIC BACKLIGTS' mode, see page 36 of user manual: https://cdn.badcaps-static.com/pdfs/...45d25a9b6a.pdf
Speaker is down to zero. Dynamic contrast is off. Dynamic backlight is off. Now the buzzing sound gone way lower.
Re: higher standby voltage on a phillips tv power supply
Is that a crack on the transformer. Others have had ferrite transformers that have cracked possibly from overheating of the windings. There is a post on the forum regarding this issue.
Is that a crack on the transformer. Others have had ferrite transformers that have cracked possibly from overheating of the windings. There is a post on the forum regarding this issue.
Haha no. Thats just a scratch. Seems like an aluminum plate to take heat.
Re: higher standby voltage on a phillips tv power supply
1) If you push the transformer body with wooden stick, does it change the pitch?
2) Monitor the PFC Boost Voltage on the main filer cap to see if it is around 380 ~ 400VDC and see if it goes up and down with the buzz level, do the same on the 24V output. see if it goes up and down too.
3) Check the DCV on the connector CN 4 Pin 10 BL-DIM1 when you change the brightness or contrast setting to see which one affect the BL-dim control signal, you need to use static Video source to do this test, also turn off Dynamic backlight.
1) If you push the transformer body with wooden stick, does it change the pitch?
2) Monitor the PFC Boost Voltage on the main filer cap to see if it is around 380 ~ 400VDC and see if it goes up and down with the buzz level, do the same on the 24V output. see if it goes up and down too.
3) Check the DCV on the connector CN 4 Pin 10 BL-DIM1 when you change the brightness or contrast setting to see which one affect the BL-dim control signal, you need to use static Video source to do this test, also turn off Dynamic backlight.
Ah finally. Its this fella thats making the noise, not the big one. When i press this guy with a stick, sound stops. And also what suppose to be 24v is showing 25.3v. Is that normal?
Re: higher standby voltage on a phillips tv power supply
That is one of the two Boost converter inductor that boost the Voltage to drive one of the two LED strings, this one drives that set of four wires counting from the left of the LED connector, the 4th wire has long exposed wire that I mention before.. Some one trying to fix that section may be that is why the wire is exposed like that, no way the insulation of the wire can be that much removed by itself.
Jut swap that inductor with another inductor to see if the noise will move to the new location or not first.
BTW, you should put insulation tape on that exposed wire before it is shorted to the chassis and causes damages.
Also look real close to see if that exposed wire is still properly crimped to the terminal.
"what suppose to be 24v is showing 25.3v. Is that normal?" That is fine, it is not tightly regulated power supply.
That is one of the two Boost converter inductor that boost the Voltage to drive one of the two LED strings, this one drives that set of four wires counting from the left of the LED connector, the 4th wire has long exposed wire that I mention before.. Some one trying to fix that section may be that is why the wire is exposed like that, no way the insulation of the wire can be that much removed by itself.
Jut swap that inductor with another inductor to see if the noise will move to the new location or not first.
BTW, you should put insulation tape on that exposed wire before it is shorted to the chassis and causes damages.
Also look real close to see if that exposed wire is still properly crimped to the terminal.
"what suppose to be 24v is showing 25.3v. Is that normal?" That is fine, it is not tightly regulated power supply.
Ok, swapped the inductor. Now the sound is back to this side So its confirm the inductor varnish id dried up. As for the main caps, on both are 386V. Already insulated the exposed wire. Yes the exposed wire is properly crimped to the terminal, add more, i just resoldered it. to make sure its not loose.
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