Predicta Contrast Lines / Streaking Issue

[Tom Albrecht]

For C19, 82 pF is definitely too much, and you'll see some loss of sharpness. Around 30 pF attenuates the faint white line quite a bit, and barely impacts the sharpness at all.

For C20 and C24, you'd probably need to increase to something like 0.22 of 0.47 uF to really see a big difference. Still, this is a design alteration, and while it might be a Band-Aid, it may not be really fixing the root cause of the problem. To some extent, these sets from this era simply have this kind of problem, although this one looks worse than usual.

The ETF link a couple of posts above has the full schematic for those that want to look at the video amp circuitry.

[Jon F]

Thanks Tom, maybe I will just do the 30pF mod and leave it be. The predicta still performs better than my other in process restorations so far so I can't really complain about that.