K7000 25" P538 after tube swap

kpfalgout

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So I rebuild a k7000 p538 chassis with new cap kit and flyback. I got an r25gygy television tube. I can't get the image centered on the tube. I can change the v pos pot to the max and still not centered, about 2 inches of black on top. The v height pot will Increase the image to fill the size but then the bottom is outside the screen.
 
Have you tried adjusting the frequency pot? It's this guy right here, might be why your image is short vertically or "rolled"

If not, R80 is a resistor in the area that you might have to reduce from 4.6 ohms to 3.3 ohms 1000025313.jpg
 
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So I rebuild a k7000 p538 chassis with new cap kit and flyback. I got an r25gygy television tube. I can't get the image centered on the tube. I can change the v pos pot to the max and still not centered, about 2 inches of black on top. The v height pot will Increase the image to fill the size but then the bottom is outside the screen.
Q9 could be bad. I've had a number of K7000s where I couldn't get V. Pos totally perfect, but some like your issue where I had to replace Q9. there's other instances where replacing Q9 doesn't fix it (hence why I lived with it being slightly off, you can adjust V. Size to get around it) but I never really looked further into what was actually wrong.
 
Are you using the yoke that was on the replacement tube or an original K7000 yoke? If the former you may need to change some component values to compensate for the different yoke.
 
Are you using the yoke that was on the replacement tube or an original K7000 yoke? If the former you may need to change some component values to compensate for the different yoke.
The problem is the horizontal position. The image on the screen on the right has a black section about 1 inch, but the left is perfect. I already tried the horizontal position behind the flyback only moved the image about a 1/4 inch. The tube and yoke are from a TV not an original k7000. What components I will need to change the move, the image more centered.
 
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