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I decided to bring up this old thread again, I have an odd herringbone like interference that is only in the color signal, if I turn the color down it goes away completely. I 'think" this is a 920khz beat pattern between the audio and chroma signals. I have already adj the 4.5mhz trap a while ago, I don't think its that. I did notice a screen decoupler cap (4uf) off an audio IF tube, its on the 250v which is shared by the color circuits. I think maybe if that cap opened up it would allow the power supply to have some 4.5mhz noise on it.
Normally I would just tip over the set and pop off the service saver cover but this beast is no fun to tip over.
Anyway maybe I will get motivated enough to do it. anyone else here fight the 920khz pattern in the chroma? I suppose it could be an alignment issue but its really pretty bad, and I apparently already did a sweep (and had a decent pic) some time ago based on re reading this thread.
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