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Old 04-15-2020, 10:36 PM
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Join Date: Jul 2004
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Quote:
Originally Posted by trinescope View Post
I finally found the color sync problem, it was due to flaky ceramic capacitors in parallel with the 3.58MHz oscillator coil.
Hooray!

Quote:
Originally Posted by trinescope View Post
I do have what looks like a bit of ringing in the picture, but it's really not noticeable most of the time. The signal looks great coming from the video detector but has the ringing at the delay line, and it seems to be the 6BK5 line driver stage that has the potential problem, or at least it was designed with this kind of response.
If the ringing appears at the input of the delay line (plate of the 6BK5) and there are no off-value components there, then it may be designed in, a result of the 3.58 MHz trap in the cathode. If you have a DVD with an Indianhead test pattern, you can look at the resolution wedge to see if the ringing frequency is the same as the chroma trap frequency.
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