I found that Shorted (K2647) MOSFET in primary section of SMPS resistors 1 ohm and 10 ohms open/burn. i try to replace then check all the primary components. all are ok but still no oscilation. i check linear side of the power supply i found 300 volts DC in Filter capacitor.
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check the speaker/s. If found OK; check and replace the damaged component/s at its audio output section circuit board. If needy, replace this board as card basis. If you wish to get some details; check the site linked here. Pull up older posts. Search the site by type in the "brand name" to your device; in the "Search box at the top right of the display window of the Homepage" to get gathered related posts. http://electronicshelponline.blogspot.com/
This is the related audio output section circuit to check.
Try this: unplug the set and wait about 10 or 20 minutes. This is to make sure that the main power supply filter caps completely discharge. Look on the power supply board, close to where the AC cord attaches to the board. Look for a white resistor labeled "0.1 OHM" (the symbol for OHM, like an upside-down U) and measure it with your ohm meter. If it is open then your switching transistors in the main power supply are most certainly shorted. Older sets had 2 separate transistors on little heat sinks labeled "C4834", then they switched to 2 transistors in one package labeled "MX0841" or "MX0842", and then some sets went to two separate MOSFET transistors. Measure those parts and post your results and we will guide you from there.
Check if Horizontal ouput is shorted.Check if you have B+ (135VDC) power supply and secondary supplies working(12VDC, 5VDC) and check if you have horiz. drive pulse from drive transformer.
A common fault for dead set is the capacitors in the power supply (secondary of transformer) - no 12VDC supply.
you should of recived a 0.01ohm resistor it is wite and sayes sony on it.
its a flame proof resistor that needs to be the very same
look for it on the pcb test it its probly open right.
ask them to send you the right part.
it's very difficult to give the exact value of that resistor.,but i can give some tips to find the value of the said resistor .( find how the resistor works, it is a dropping or fusable? if fusable used .47 or 1 ohm resistor if it is a dropping resistor you should make a trial and error .from 100k,10k or 1k.
h/line is due to vertical section failure.
1 reduce brightness as you will get h/line due to vertical failure.
2 check v/section for loose contact or yoke connection.
3 check supply to vertical section.
4 check associated parts in v.section
5 at last check for vertical ic.
resistor R410 CONNECTED TO high voltage transformator T444 is low value resistor.
.5ohm to 10 ohm.
it burnt again due to short cht in vertical mainly due to ic.
hope this will help.
as per schematic diagram go to