AFTER BEGINING WITH SHORT INTERVAIL MY PROJECTION TV STOP NO PICTURE OR SOUND
Hello,
First lets look at what your problem is: The TV set is not coming on. First check for open fuses, to do this: unplug the Tv and with your ohmmeter set to 1xR test across the fuse this should yield a reading of 0 ohms, be sure to check all of your fuses there might be three of the (switching power supply fuse, High Voltage power supply fuse, and a deflection circuit fuse). After checking the fuses, then check your Horizontal Output Transistor(HOT) (now be careful here, because the HOT these days could be a high power MOSFET or an actual Bi-Junction Transistor(BJT) with the damper diode and resistive element built in ) In both cases you are trying to see if the collector (BJT) or the source (P-Channel) Drain (N-Channel) (MOSFET) is shorted to ground. In which case you will have to replace the Transistor or MOSFET (which ever one you have).
Now for a reality check: If that Transistor or MOSFET is bad you are in for a surprise if you just change out the component, the reason I say this is because the primary of the Integrated High Voltage Transformer is usually in series with the HOT or the MOSFET, meaning any current that flows through the HOT or MOSFET is going to flow through the primary of the IHVT. Now for your sake I would suggest removing the IHVT and doing three tests on it, the first test is a resistance test of each of the associative windings to make sure you don't have an open in the windings (I say open because most of the time finding shorts this way is not easy, due to the windings not being that long. The second test is a capacitance test between the anode of the IHVT and the ground lead of the IHVT this should yield a reading of 1.5nf to 6nf depending on the Transformer. The last test is called a Damped Oscillation test or a Ringer test, this test produces a damped oscillation which should produce a clean damped sine wave with no flat areas. If any of these tests fail replace the IHVT.
Now as far as the Trippler test it only by using a High Voltage probe, in fact this is the only test you will be doing with the power on. Testing the trippler is easy after you are sure the other components are working, turn on the TV and with your high voltage probe test the input of the trippler and then test the output the out should be 3X the input.
Now if you don't have the equipment needed to perform these test, please take your TV to a qualified TV repair shop and have it repaired by a TV technician, because this section of the TV can kill you, if you make a mistake.
I hope this helps,
Thank you,
Shuttle83
Its not the hoz output dont listen to this pleb...if the tv was coming on and then going off at regular intervals then it is the RF power transistor. you will find it on a metal heat sink within about two inches of the tripler,(the cylinder with a red HT lead going into 1 of the colour guns). you will need multimeter to check on diode test,check the reading between all 3 legs IE; the base collector and emitter. if any of the readings are 000 then that is the prolem it has an open gate
I need m# if you don,t have eny power noled in front of tv a green lite ck out fuse if that good. ck hozoutput it by the flyback most of time if the hozout is bad you should replace flyback the part#
is on the side a tag.the hozoutput the # you can se it. if you have a onm metter you can ck the hozoutput in dioe mod.
i till you this you can call me if yon need to 518-798-7560 ask for robert i see what i can help you?
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My goodmans lcd is doing this.
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