Question about Philips 20PT643R 20" TV

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Tv not coming on

Im having more than 95 volts on the line regulator of the TV and the LED is lighting when I switch on the supply.

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  • Joe kulula Sep 23, 2008

    Thank you for the solution. It gave me a way to the fault but i need more help on the voltages from the power supply. What are the common standared voltage for philips TVs? ( Like this model 21PT3324/56R ). The TV is blowing up the HT regulator a BUT 11 AF


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Your TV will probably not work on 95 volts. It may even damage your set. To see if your TV is still working properly you need to find a source of 108 volts at the minimum. Why is your voltage so low? Are you using a meter to check it?

Posted on Sep 18, 2008

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My Sony Trintron's LED Light blinks 9 times when I try to turn on the set

  1. If it is intermittent 9 blinks, meaning sometimes the TV comes on and other times you get flashing, then change the switching regulator on the "G" board or check connections. Make sure the regulator is -12 or -13 (negative). If you wish to get more details about the blinking codes to Sony brand TVs, check this link. Pull up older posts there.

Mar 04, 2013 | Sony FD Trinitron WEGA KV-32FS120 32" TV

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Here is a troubleshooting guide for you:

Flyback Transformer

Check the 200V line on the CRT Board, it could be 170V also,

meaning the flyback is not oscillating.

To have the TV working, it should have at least a B+ of 95V

Check the main regulator.

Maximum supply voltage is about 135V on some TV models.

Sep 22, 2012 | Televison & Video

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Sony wega flat screen power problem. does not turn on led red power light blinks 2 seconds and then truns off again

The problem of your TV is in the power supply section.Maybe the regulator is deffetive thats why the power supply not comes on.Its maybe also the harizontal output transistor is deffective.So check the regulator an harizontal output and replace if deffective..

Sep 19, 2011 | Sony FD Trinitron WEGA KV-32FS120 32" TV

1 Answer

Light blinks three times on my sony wega tv model #kv-32hs500 but will not come on .

Three times blinking denotes that there is some overvoltage in the secondary DC supply rail inside your TV. It is called Over Voltage Protection [OVP]. Due to this fault as soon as the set is switched on, it goes to standby state and the front LED blinks tree times, and won't come up again.

It may be due to power supply regulator section fault inside your TV. To find out you have to open the back cover of the TV. As high as 32KVDC [32,000 volts DC], points are there inside your TV, while it is working, all care should be taken before open it. Even though the TV is switched off, the final anode of the picture tube will have a charge upto this voltage for sometime and it is dangerous. So be care.

After opening the TV, locate the power regulator section. It can be easly located, that the AC input goes to that section, after the switch connection. You have to pull out the printed circuit board and should keep it upside down for repair work. During this time, sometimes you may have to unplug some plugin connections from the board, and keep it marked, so that you have to refit it there later. You must have some concept of soldering and more patience to do this work.

After the board has been pulled out, loate if there is any soldering loose contact to the regulator Ic or its nearby components. As they will heatup during working, continous heat up and cooling may make some of the solderings, and it is normal in practice. As it is very difficult to locate the loose solderings by naked eye, resolder all suspected points with applying a little bit of extra solder. Never make any short between them while soldering. Normally this will rectify the problem. If it does not help, replace the power regulator with same type and number; [ Normally in Sony sets they uses STR type regulators on power side], and it is a very stable and High Accurate device, and should be replaced with the same type and number.

Check if now the secondary DC voltage at the secondary voltage rail of your Tv. Now it will be zero due to overvotage shutoff. Locate the pin to which the DC power goes into the LOT [Line Output Transformer], and make a small break on its print that carries supply to it. Be sure to make a small break, as we have to rejoin it after the fault detection. Connect a 100W filament type bulb between the DC supply Rail and to the Negative. Switch on the set. The bulb will glow, and take the votage across its filament. It should be between 125 and 130VDC, for 32" Sony TVs. if it is found abnormal, you can make sure that power regulator section has some trouble in it. Three blinks shows that symptom in Sony TVs. Ok.

Oct 31, 2010 | Sony Televison & Video

1 Answer

Have a sony tritron wega flat screen tv and it wont turn on, its red light blinks three times, what is the problem and how do i fix it?

Your TVs horizontal output stage is not working. That means, the line output side [LOT and related components], are inoperative. It may be due to some secondary missing voltages from the power supply section of your TV. There may be some open resistor, or short inside the Line Output Transformer [LOT] itself. Anyway that side is not working. Your TVs power supply regulator system has no trouble. It supplies the required voltage to the other sections. That is why you see the LED [Light Emitting Diode], fitted in front panel of your tv blinking for some time and shuts off. As soon as the TV is switched on, the power regulator system inside the tv will supply all the necessary secondary voltages to all sides. If at any section misses the required voltage, the system control Ic will detect it, and will try to rectify that. It is so programmed at the factory. If it can't do it, it will automatically shuts all the supplies from the power regulator system. It is a protection added by sony to all models of their Tvs.
You yourself cannot detect and repair this fault. Get the service of an experienced technician.

Oct 17, 2010 | Sony FD Trinitron WEGA KV-32FS120 32" TV

1 Answer

The standby light flashes and the tv will not come on

check the power supply, its not giving out the required voltage output. if you cant repair a tv plse take it to a workshop, ask a technician to make sure that he checks the following components.
power diodes and transistor, fusable resistors around the power supply, and zener diodes.
he should make sure that an ht of 95-110 volts appears on the line transformer. later a transformer will produce various voltages to trigger other voltages to open up your tv. thanks

Mar 26, 2010 | Sony FD Trinitron WEGA KV-34HS420 34" TV

2 Answers

The power comes on and then turns off and the front green power light blinks.

There is a small IC in the power supply section,
not the IC regulator that's the problem.

Jan 06, 2010 | Philips 32PT6441/37 32" TV

1 Answer

No picture or sound

i think the light u see is the standby indicator diode. take your tv to w/shop, the technician will know how to test the following
tube so called bulb using a different mother board card, and also test the mother board using a different tube ( tv bulb)
test the power supply out put 95 volts to the line tranaformer which will give you different voltages 5, 12 and so on.
the isolation methode will help us trouble shoot the problem, we should not be rigid on one part only.


Jan 05, 2010 | Panasonic Televison & Video

4 Answers

AIKO TV problem

when switched on, the stby LED comes on it is indication that supply input is there. the problem could be in no output from regulated output supply in your tv. if it is ok then horizontal section is to be checked.

Sep 16, 2007 | Televison & Video

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