I would like to slightly move yoke to get horizontal (topleft) to behave because pincushion does not get me where I would like to be when adjusting convergence in course adjustment. I'm not sure how you would move top of yoke without loosening clamp.
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With your TV in setup Use a small magnet to "move" the non converged Red, Blue, or, Green color lines "crosses" (each CRT will need to be adjusted in turn) by moving the magnet close to the offending Red, Blue or,Green color CRT yoke or, tube while observing the movement of the CRT color line "cross" in a mirror ( try several places near the tube and, several strengths of magnets:) a refrigerator sheet magnet works well (you can cut these with a scissors to make a better fit or, apply less magnetic "pull." by making them smaller (you may need more than one magnet per tube to fix each CRT's convergence) When you have each CRT tube's convergence right, apply some clear silicone adhesive to the magnet and, permanently affix the magnet to the now "fixed" CRT tube exactly where you placed the magnet to obtain the best convergence on the CRT. (Do not adjust the "Green" CRT unless you must, as it is used as the color line to adjust other lines to)
makenamicro, there is still a convergence yoke the green crt which means there is still a drive control circuit that controls your dynamic and static convergence. If you are working with out a service manual it is still possible that one of the convergence power amps is out, since you mentioned that you can adjust the red and blue to conform to the green pattern then try to adjust the green with out the R/B present if you ca not still adjust you green pincushion problem then suspect one of the power conv amps or a defective green conv yoke.(don't forget to check the small value resistors usually around 2 ohm and the pico fuses if the tv uses them. good luck and i hope i answered your questions, please let this web site know if yes by leaving some pos feedback. thanks!
Symptom: Unit appears to have poor convergence due to: 1. cross hatch appears tilted 2. one color (or more) being larger than the others.
Cause: The yoke or yokes may have: (1) rotated slightly or (2) slipped down during transport.
Resolution: Loosen a yoke and lower to inspect the tape. If black tape is present remove it from under all yokes (white tape or no tape is OK). Slide yoke or yokes up tight against the CRT and tighten to prevent slipping or rotation. Precede with alignments and or convergence as necessary.
You don't adjust convergence through a service mode on one of these sets. With a conventional CRT, convergence is done by physically adjusting the convergence rings on the neck of the tube, and the position of the deflection yoke near the bell. You would also need a crosshatch generator to provide the required test pattern for adjustment.
The pincushion it intimately related to the horizontal circuits,the electron beam must travel farther to reach the corners of the crt and it does to the middle and so without pincushion circuits the raster would be bowed in on the sides on crts 27 inches are larger.Pincushion corrections straightens the raster by modulating the horizontal yoke current at a vertical rate.In an RCA tv the pincushion circuits are usually numbered 4800and the pin amp will probably be numbered 4801,its drive transistor should be Q4802,R4802 will be the width control,and R4805 the e/w pin amplitude. its inputs from the vertical should be Q4801 (subtractor) Q4803 (buffer) you should have a parabola waveform at 4801,yoke current can be modulated here without effecting high voltage.when Q4802 conducts voltage should decrease across Q4801 and the voltage drop across the yoke increases. The east west pin amp control 4805 controls how much of the vertical parabola is input to U4801 to compensate for changes in width caused by variations in beam current.By varying the e/w control resistor you can know if the circuit fault is in the input or output,if the picture varies in size the fault is in the input to U4801,if it does not vary check the output or U4801......hope that helps
are you sure it's yoke? these are know for bad convergence amp ic's other wise it's a screw and glue holding the yoke in place loose the screw and try to break the glue with out breaking the plastic on the yoke, the other thing you can do is adjust the magnets which have tabs on the yoke. i would mark the position's of everything on the tube with a sharpie so you can get it back to start.
Convergence amp ic bad http://home.earthlink.net/~oleg.filippov/ConvergenceFix.htm http://cmpalmer.blogspot.com/2006/11/fixing-my-own-tv-part-ii.html Sony Convergence http://www.techlore.com/blog/entry/19694/Sony-Convergence-Repair-My-Sony-TV-has-a-distorted-picture-/ http://www.techlore.com/article/19631/Sony-Convergence-Procedure/
go back and check them resistors....with a magnifier and be sure of the color codes...I bet one is way off. and get the manual out confirm each resistor u replaced and even remeasure it. dont mess with yokes or nothing on them tubes! its on the board....check for solder splash too on bottom or shorted pins on stks.
if you must just make a big x on screen from corner to corner now cover red and blue tubes. the green should be in center of the x if not move the adjusting 2 magnets near yoke to center it
it will have tabs sticking out u might have to move both. after you center adjust red and blue to green.