K7300 All Red

jjhudgins

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So I don't work on these very often, but find myself scratching my head.
-The image is all red.
-I get full raster and all the pots on the remote board work. Except for contrast and brightness.
- the board has new caps
- Perfect b+
- I've changed out the RGB chip LM 1205
- I've also changed out la7851
-i'll swapped neck boards from a working chassis
- none of the color transistors taste bad
- there's nothing wrong with the tube as it's my k7000 test tube
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Not sure what is going on but I'd start testing on the red line components up to pin 4 of I201 and then out of pin 26 of I201 to W501A. I'd hit connectors W301, W501A and CN501B with a reflow for good measure and check those pins for continuity. I'd check the .1uF mylar caps on the red clamp and drive circuits too.
 
That looks like magenta (red + blue) to me. Check resistance to ground of the LM1205 RGB output pins (26, 20, 17), of the positive sides of C301, C304, C307 and of the emitters of Q301, Q302, Q303.
 
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