Sansui sv29276 keep on blowing transistor D1556 (hori) i have replace transistor and line output transformer it plays for about 30 sec then it blows again. can someone pleace help me ?

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.
http://electronicshelponline.blogspot.com/
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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. Surf the site with patience. Pull up older posts.
http://electronicshelponline.blogspot.com/
Desolder out the horizontal output transistor, and now power on the set. If the set now powers ON, replace the horizontal output transistor. It is faulty. [Collector to emitter or collector to base leak]

Try using a higher voltage for the replacement cap. Usually factory uses exact voltage but that can not handle surges.

check fly back cap & eht transformer

the 4498 that is top left in picture, but is the transformer there burnt or just real dirty?

These sets had alot of problems with bad FBT flyback tranfomers,You might need to change FBT.
Heres another thing they also had Bad Picture Tubes that will blow hori output and you will not know its the Tube untill you replace the FBT.Use a high voltage probe to monitor Voltage coming from the anode button, if you dont have a HVP then disconnect the CRT board and monitor set.

The horizontal output can be open and the set wont have High voltage or it can short which will usually blow a fuse. The transistors cost about 10.00 - 12.00 for quality Horizontal output transistors.

this is a normal behavior if one of the power supply transistors have blown. take the unit to an enlectronics repair. they can either change the transistors affected (usually more than one) or replace the power supply board.

Can you please post the make and model. That would help u sto provide you with more details.

Thanks,
Dan

Look for shorted output transistors or possibly shorted rectifier diodes. An immediate fuse blowing up usually means that the power supply is the problem. Keep us posted.
Dan