Set switches ON without any problem, and after a second, the standby ligh blinks twice and switches OFF.
The fault is due to some shorted component/s on the main circuit board. The system control detects this situation, and switches OFF the power supply regualtor section.
Probable causes are;
[1] Horizontal output transistor [2SD2624-CA - Q801] Collector to emitter short.
[2] Fly back transformer [FBT] [NX 4751 M3A4 - T503]: Internal winding short.
[3] Deflection Yoke. Internal winding short. This is a very rare case.
[4] Any capacitors at the horizontal output section.
Check:
Disconnect or desolder out [L 600], temporarly, and connect a 100W filment type bulb across [C614 - 33MFD 160V] Switch ON the TV and measure the voltage across C614. It should be around 133 to 137VDC. Be sure this voltage is steady.
If it is OK;
Switch OFF the set, and measure the resistance to collector and emitter of Q801. It should be never show below 50Ohms. If the measured resistance shows below this range; desolder out the horizontal output transsistor from circuit, and measure the collector to emitter resistance. It should never come to Zero. If it shows no resistance [0 Ohms], make sure the transistor is defective.
But, before replacing this transistor, We have to make sure that the Flyback Transformer is OK. The flyback transformer cannot be checked by normal methods. But there is a syptom to get it.
Repalce the horizontal output transistor with a new one. Fix it with all it fixures with heat sink. REPLACE [C812 - 0.033MFD] WITH A NEW ONE as a precautionary measure; Because, if this capacitor has open circuit, the flyback transistor will blow out as soon as we switch ON the set.
Switch On the set. If the flyback transformer is OK, and there is no other shorted components in the horizontal output stage, the set must come ON without any problem.
Images of flyback transformer and horizontal output transistor are attached.
