Another Westinghouse H840CK15

[old_tv_nut]

Originally Posted by trinescope

I finally found the color sync problem, it was due to flaky ceramic capacitors in parallel with the 3.58MHz oscillator coil.

Hooray!

Originally Posted by trinescope

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.

[trinescope]

Here are the pictures I was not able to post last night for some reason. The scope screen shots show a multiburst signal at the video detector and the input to the delay line.

[trinescope]

Originally Posted by old_tv_nut

Hooray!



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.

I really believe the response is designed in, the ringing goes away if I short out the 3.58MHz trap. Like I said, it's not all that pronounced under normal conditions and video material.