My TV model no lg29fe5rge when we switch on the tv .why my tv horizontal output transistor(c6090) is blowing off??

Check and replace damaged component/s at its horizontal scan output section circuit. Check the LOT (Line Output Transformer) too for damage. Replace the horizontal scan output transistor. Check the input voltage to LOT. If the voltage is absent check the feeder resistor; if any. If you wish to get some details; check the site linked here. Pull up older posts.
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Check and replace damaged component/s at its horizontal scan output section circuit. Check the LOT (Line Output Transformer) too for damage. Replace the horizontal scan output transistor. Check the input voltage to LOT. If the voltage is absent check the feeder resistor; if any. If you wish to get some details; check the site linked here. Pull up older posts.
http://electronicshelponline.blogspot.com/ Type in this key phrase " my service table today " in the search box at the top right of the the home page, to get gathered some pages which has the details of practical experiences of the author of that site. The search result might display about 20 Nos of related posts. Press the "All posts" at the bottom of the list, then you can select them one by one.

Check the capacitor connected to the collector of the horizontal output transistor to ground for loose solder or open. Replace that freewheeling capacitor [ usually comes between 3900Pf to 9600Pf 2000V]. Replace it with an other one of same capacitance value; before proceed. Even if it blows out the horizontal output transistor; entire circuit should be checked. Check the deflection coil too for shorted winding.
If you wish to get some details; check the site linked here. Pull up older posts. Surf the site with patience. http://electronicshelponline.blogspot.com/

Check and replace damaged component/s at its horizontal scan output section circuit. Check the LOT (Line Output Transformer) too for damage. Replace the horizontal scan output transistor. Check the input voltage to LOT. If the voltage is absent check the feeder resistor; if any. If you wish to get some details; check the site linked here. Surf the site with patience. Pull up older posts.
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Type in the brand name of your device, in the search box [at the top right] of the display window, and press enter to get all related posts. It will make surf easy.

model number?little more info...first thing check for short in power and
horizontal output transistor-common problem.also bad connection
cap in horizontal output circuit can cause blown fuse

Check the freewheeling capacitor, connected between its collector terminal to ground for loose solder, or damage. Repalce this capacitor, before replacing the horizontal output transistor. If this capacitor is open, the horizontal output transistor will blow off, at the time of switch-on itself. Normally, its value will be grater than 3900pF & lesser than 9800pF[2500V]
If you wish to get some details; check the site linked here. Viewing it in "Mosaic" will make surf easy. Surf the site with patience. Pull up older posts. Surf the site with patience.
http://electronicshelponline.blogspot.com/

Check the LOT. If it is faulty, horizontal output transistor will blow out. Check the capacitor connected across the collector of the horizontal output transistor to Gnd. If it is bad, or have any loose solder terminals, H-Out transistor will blow out. If you wish to get more http://electronicshelponline.blogspot.com/ check this link. Pull up older posts there, either by its left side bar, or see it in Timslide option.

21fj8rg3t8 horizantel over heating and screen veriasion

Check all the capacitors connected to horizontal output transistor. Especially one connected with its collector to ground. a high voltage [1.5Kv]. capacitor. Replace them. Check for any short inside the winding of the yoke. It is difficult to detect the winding short inside the yoke. Connect an other yoke in place, after pulling out the CRT base card out of the TV. This you can make sure about the condition of the deflection yoke.

ALL the next is with the tv unplugged (NO NO power)

• resold the jungle (video processor) all around
• following the horizontal drive pulse path and arriving to the horizontal area just after the horizontal transformer and in the base of the horizontal DRIVER there is a electrolytic capacitor (if this chassis uses this one,) Change it (maybe is dry)
• solder all components i just told you in the last step. horizontal driver, transformer, etc
• remember:
• if a transistor is blowing with no reason (there is a reason: the collector receives 130 volts but cannot hold it forever, It has to be in some place. if the switching pulse doesn't arrive to it the transistor throws this 130 volts and burning itself. i hope it is help full.