Carbon composite in place of carbon film

[DaveWM]

the fact that the horz convergence is not responding (I think that is what you said) and the horz blanking may be causing the jail bars sure points to a problem there. Is the width ok? not too wide?

[TinCanAlley]

Originally Posted by DaveWM

the fact that the horz convergence is not responding (I think that is what you said) and the horz blanking may be causing the jail bars sure points to a problem there. Is the width ok? not too wide?

The horizontal convergence for the blue moves quite a bit, but just not in line with the other colors on the sides. There is the coil and two pots that move around the blue, but no combination of them will get the lines where they should be on the sides without messing up the top and bottom horizontal lines (center convergence stays put).

I've gotten used to no overscan, so this set's image seems too wide. I believe, though, that the overscan is about 6%. I can just see the edge of the 5% line on the overscan pattern.

[jr_tech]

I may be missing something here, but why is the scope thought to be in need of repair... the waveform posted looks reasonable, and perhaps the 10 or so "ripples" at the bottom of the waveform might indeed correspond to the 10 or so bands "jail bars" seen across the TV screen?
jr

[TinCanAlley]

Originally Posted by jr_tech

I may be missing something here, but why is the scope thought to be in need of repair... the waveform posted looks reasonable, and perhaps the 10 or so "ripples" at the bottom of the waveform might indeed correspond to the 10 or so bands "jail bars" seen across the TV screen?
jr

If you scroll up to post #53 you'll see a waveform I posted. The waveform for the 170V in the pic is what supposed to be on the scope. I thought I had it, but that waveform didn't go away when I removed the probe. So it most likely isn't from the circuit, but from the scope itself.

I recalibrated the scope per manual and I was able to get both of those waveforms in the picture from the SM. However, all other attempts to scope out other points has given me garbage on the scope. I think there might be a short in the 10x probe.

[jr_tech]

Originally Posted by TinCanAlley

If you scroll up to post #53 you'll see a waveform I posted. The waveform for the 170V in the pic is what supposed to be on the scope. I thought I had it, but that waveform didn't go away when I removed the probe. So it most likely isn't from the circuit, but from the scope itself.

I really suspect that the probe could have been picking up the waveform without direct connection to the test point... a sensitive probe held near the horizontal section can easily do that. If you turn the TV off, does the waveform on the scope stop?
jr

[TinCanAlley]

I managed to get to good waveforms from the convergence section (easiest to get to and many test points). The forms matched almost completely. Then things went wrong. I think there's a problem with the 10x probe. It's a heathkit, so I'm going to take it apart and see what might be going wrong.

[DaveWM]

if you are getting good wave form the 170v pp then trace on through and see if you can see it getting to the base of the blanker