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Re: 0 volts on pin 9 of the flyback
Base on the service manual information, yes IC561 could be defective.
You did not get the +15 volts because the TV failed to power up and the majority of voltages are coming from the flyback transformer.
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Two basic ways--most shops use a ringer---with flyback out they connect across the primary (where sweep transistor collector goes to where that lead on the transformer exits--a good bad indication is seen.
Second way is voltage into the transformer is tested and High Voltage is measured at the CRT---usually if transformer bad you will have 4kv or so (4,000 volts) and the suspect is clear.
If HV just comes up full (over 20 Kv) and drops to zero it is not the problem and something is shutting the set down.
I want you to know I have been where you are on this same TV and what I found is there are three ICs all in close proximity on the SIGNAL BOARD that I recommend strong you try REPLACING all caps on the ICs as follows:
IC2P02--12 volts input and 9 volts output change C1P01 on input 47 mfd/35 volts change C2P03 on output 100mfd/16 volts
IC2P01--11.9 volts on input and 9 volts output change C2P04 on input 47 mfd/50 volts change C2P05 on output 100 mfd/16 volts
IC2P03--4 volts on input pin 5 and 3.2 volts on output 1 and 3.7 volts input on pin 2 and output pin 4 is 3.2 volts. change C2P07 47 mfd/35 volts change C2P09 100 mfd/16 volts
I know this is a bit technical but it is what is wrong with your set. Caps have polarity (positive and negative connections) They all must be unsoldered and new ones soldered back
The Signal Board usually has the tuner on it where the coax connects. The board needs to be removed by unplugging it to change the caps.
maybe your flyback. check b+ on the flyback. If you dont have voltage you can unsolder b+ pin on flyback and feed a 75 watt lamp to verify if power supply or flyback trouble.I think it`s pin 9 on flyback. look for print b+ on pcb.
in theses set's there should be a board that has a module that the power chord plugs into this module supllies the motherboard and the componants on it. to be honest it would be best to just let a professional replace any defective chips orboards at this point because i believe it is not just one problem but several and without me beibg hands on it would be difficult to narrow it down to just a simple answer.
Check for +15V from the flyback pin # 9, if that voltage is present; check R541 and D531. If these parts are good you should find +12V at TP98 nearby C539.
If still not voltage found, I would suggest to desolder and isolate IC561 pin 2.
hi the problem you are having is going to be one of the most common problems with that type of telly the problem is going to be the flyback transformer needs replacing and also the transistor neads replacing its the one located nearest to the flyback transformer and it will be on a heatsink. If you are unsure what im telling you then you shouldnt risk the repair yourself as the telly has power stored in it even when its unlpugged it might not kill you but you will get a nasty shock as the voltage is amplified inside the telly so is greater than 240v so dont mess with it unless you are sure what you are doing. If you are doing the repair yourself then you need to get the schematics so as you can get the test points that you can test using multimeter and osciloscope this telling you whats exactly wrong as a resistor or two could have blown when the transistor failed also the schematics will give you part numbers. The transistor and any resistors are easy to replace but you nedd to protect the new ones from heat damage when soldering the new ones in you need to dispurse the heat using clips or something similar. Now the difficult bit is unsoldering the flyback transformer this carrys high volts of electric and will give nasty shock if you dont dispurse the electric charge first you need to short across one of the caps to earth but you need to know the right one. to remove flyback it regiures alot of unsoldering and resoldering possibly causing damage to the new one during soldering is easily done. If you are going to get someone else to do the work like repair shop your looking at about £45 uk or $80 to $90 us so you need to think is it worth it let me know if you need further assistance ok
When the horizontal output (2SC4927) is shorted it means one of 2 things is wrong - the horizontal drive transformer has cracked solder joints or the flyback transformer is shorted inside. If the solder joints on the horizontal drive transformer (the small grey transformer connected to the base of the horizontal output transistor) are cracked then the set will play for a little while and then the parts you just replaced will again be destroyed. ALWAYS resolder the driver transformer when replacing the parts you mentioned! When I replace the parts you mention and I do not see any obvious cracks on the driver transformer then I unsolder the B+ pin of the flyback (labeled 135, for 135 volts) and put a 60 to 100 watt lightbulb (drop-light) in series with the flyback. This means that the 135 volts B+ goes through the lightbulb and then into the flyback, so the lightbulb acts as a current limiter to protect the horizontal output. When you turn the set on the bulb should glow no more than about half bright and you should hear the high voltage come up, but you should not see a picture. If you turn the set on and the bulb glows as bright as if it was plugged into the wall then you can bet that flyback is shorted and must be replaced.