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I would guess you do have audio. The solution is to pull the convergence,power supply board out. You must scrape all the varnish (brown film) off the board on the solder side. This varnish may conduct and create a high voltage shut down in your video. Then you must inspect the rest of the board for bad grounds. You will need to inspect any and all ICs mounted on heat sinks. The pins may have separated from a good connecting ground on the board. You must really, really look for cracked rings on transistors, diodes, capacitors and resistors etc. Resolder as necessary and do not short pins together with too much solder. Thanks for asking and show all hands of support!
Your problem will be in the power supply of this TV. It will be the board that has the flyback transformer. You will have to pull this board out and find the vertical IC. I think it will be of the LA78XX series. You will have to resolder this IC, and don't exceed the solder. You do not want to weld the pins short. Next replace any and all capacitors near and next to this IC. Could be four caps you replace. As for the dark picture, you will have to inspect the rest of the power supply board for bad grounds (rings around the pins of capacitors, diodes, transistors, resistors and any other ICs mounted on heat sinks. Check your capacitors in the rest of the deflection area, and replace as necessary. Inspect those jumper jacks( that connect to the signal board), these will almost always need resoldering. Now the the other half of the the TV will have a signal board. The signal board will need the convergence IC resoldered. The IC will be of the STK-392-110 series. Solder these pins and do not short them with excess solder. This area will also, sometimes, provide the dim picture you describe. Inspect the board for any and all grounds. Be sure there are no rings around any component soldered here as well. And once again, inspect the jumper jacks (connects the two boards together) and resolder as necessary. Seems like a lot to do and there is. I hope this will help you with the start of repairs. Thanks for asking and show all hands of support!
By now this aging TV has many, many bad solder grounds. The first place to start, is to pull the convergence board out. You will see an STK-393-110 that has rings around the pins. This is bad grounding. Please resolder this, and do not use excess solder or you will short the pins together. Then you should inspect the board for any and all ICs attached to heat sinks and resolder the pins to the board. Look for bad grounds on power resistors, transistors, diodes and capacitors. Also resolder areas where the board meets the other board. These are jumper jack connections. These can be a problem, solder as necessary. The second board to inspect is the power supply. It is the one with the flyback transformer. The first thing to find is the vertical IC. This is usually the reason you have no video. Please resolder the pins of the vertical IC.Do not to use excess solder or you will short the IC. Resolder the flyback transformer,horizontal transformer,power resistors, capacitors, transistors attached to heat sinks etc. Resolder the jumper jack connections that connect the boards etc. I cannot say enough, you must really inspect to find these bad grounds.I do not believe you need to replace any parts now. Just resolder and reinstall. This will take great patience and skill. Thanks for asking and show a few hands of support!
wow, good luck with this one, many repair shops end up with these tv's and the owners don't want to bother with them when they find out how much it will cost to fix them. that being said, get on the phone and call a few and you may find just what you need, another alternative is of course the internet (try sears parts store), or Ebay, hope this helps. I like you fix old stuff and enjoy bringing things back to life. good luck
For starters..Your convergence board is my first concern. If you can pull the board out, do so with great care. There are many, many bad grounds here by now. I can not say this enough. The convergence IC has been separated from the board. Examine the pins and resolder as necessary. Do not over solder, you do not want to solder the pins together or you will create a short. This goes for any IC with pins you resolder. Check the diode connections, resistor connections, jumper pin connections,connections where cables jump together between boards, capacitor grounds. If you can, check all electrolytic capacitors with an ESR meter, and replace capacitors as needed. Heat sinks will need resoldered tightly to the boards. Start with this and see what happens. There is much to do, with the one board. The next board will be the power supply, and you will have to repeat the effort just mentioned. But, try the first plan and see what happens.
Try to check the relay in your power supply, it might have a loose solder or loose connection at the back of PC board. The sound that you hear when you plug is the relay itself. if your set newer , check for loose connections on pins and other connecting parts of relay. That is located in the power supply section. If nothing happened after resoldering, then replace the relay, probably the contact points is corroded or damaged.Hope this will help...pls. send feedback so we can work together.. Thank you....
you are so lost... a short in anything after the power supply will shut down the horizontal driver signal. first check to see if horizontal
output transitor is shorted. If not it should have about 110 volts dc on it. if not go back to
Power suppy ...many things start here...check to see if you micros got power a 5v heatseeked regulater is common bad. also the startup circuits can be tricky...in the power suppy.
I look for a kit online for power supplies ...they give you about every that fails.
or you can start buying boards...best bet it is take to a professonal for you my freind havent a clue.