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Re: Re; Model # AV27765
Wait one second here if the ic wasent producing horiz drive you wouldny be getting any picture.. Your saying the set is floating the picture side ways?? your gonna need a scope to see where your losing the horizotal sync pulse from my friend.. No insult intended but if you have no horizontal drive there would be no High voltage therefore no picture.
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If rolling in a right to left and not up down it is a sync problem--horizontal sync comes from one of two places in general---a pulse off the high voltage transformer or directly off of what is called in the trade the Jungle IC.
That is not a joke--Most of these sets use a large IC (63 pins or more not unusual) that contains: color, video, vertical drive, ABL and much more---so much is crammed into that chip it decades ago was named the Jungle for clear reasons.
A schematic and or scope may be needed to trace and find what is bad.
if off the high voltage transformer (more common in old sets than new ones) it will be a open resistor.
If at the jungle you would have to go to the pin with the sync and follow it out to see if none at source or if lost somewhere down the stream.
You're either losing high voltage or power supply is not producing the horizontal drive signal, Check for 130v on the collector of the horizontal output transistor, if you're missing your voltage, you have a power supply problem. If voltage is too high you have something open in the power supply such as a low value resistor. If its low, something is shorted in power supply, possibly voltage regulator ic.
Your TV suffers from horizontal phase shift. It may be due to the Ic fault or horizontal output sync: signal from the LOT not reaches to the respective pin of that Ic. Check first whether the horizontal sync: signal from one pin of the LOT reaches to the sync: pin of the Ic. If you have a frequency meter the thing should be easy.
Most common is IC fault.
The probable defective part is the vertical IC. If changing that does not resolve the problem, check the capacitors in the same circuit. Also, check for the proper voltages at the vertical IC. If the IC is not being fed its power, it won't work either. I don't have a listing for your specific model. If you can post the vertical IC part number (LA7837 for example), I can list the voltages per pin.
The 8V at pin 36 won't show unless there is oscillation, the primary voltage pin is pin 10, 8v. Don't mind me asking, you have checked the B+, right? Because the blinking LED is often because of power supply problems. And if that's okay, desolder the horizontal driver output legs and connect an LED to find if it is oscillating, if it does, forget the ic part and move on with the FBT and things. Good luck.