K7400 no brightness control on remote board

kpfalgout

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So I have a k7400 25" that was dead, I did a cap kit, flyback and the b+ pot. Chassis is up and running but i have no brightness control on the remote board. I do have contrast control but i get a split in the color. See photo. I can get that line to go away adjusting the contrast on the remote board. I can change the screen pot on the flyback and that works. I know its not the tube, cables and neck board, I have another k7400 no split in contrast and has brightness control at the remote board. I did notice that the working board doesn't have c734, so i removed that cap from the nonworking board still nothing.PXL_20250718_224652322.jpeg
 
Check for cracked solder joints. One of the resistors might be broken loose.
I just reflowed all the solder joint on the chassis board. Still the same problem no brightness on remote board and the contrast split.
 
Problem solved. Resistor 310 was not in circuit which is a jumper. That solved the brightness control and that split contrast. Thanks again for everyone's help
 
your picture is rotated 180 degrees. are you using it in a mirrored game or did you just plug the yoke connections in reversed?
 
I just had the yoke connection in reverse. I was getting tied of plugging the chassis in and out trying to solve the problem.
 
I had a broken trace on the main board. That problem is solve thanks for the help. Now when i increase the brightness on the remote board i get a blue color background on the tpg. It looks like the blue is overdriven but there is no drive pot on the neck board for blue only green and red. I have a second neck board with the same cables, main board and tube no problem. So I know its on the neck board. I replaced q503, q506 and u500 still blue color picture. Any ideas...
 
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