TBC creates a vertical dotted line?

[joekalle]

Hey,

I´m using a Panasonic NV-HS860 VCR. When I´m turning on the TBC, a vertical dotted line appears on the left side of the screen. It occurs on every VHS tape I have tried so far and only happens when the TBC is turned on.

1.) Does anyone has an idea what could be the reason?
2.) Is there any way to fix/remove it or is the TBC permanently damaged.

I'm grateful for any advice. Thank you.



Screenshot 1 with TBC.png

You must be logged in to view this content; either login or register for the forum. The attached screen shots, before/after images, photos and graphics are created/posted for the benefit of site members. And you are invited to join our digital media community.

Screenshot 2 with TBC .png

[aramkolt]

Do you see that line if you watch the output on a TV or when using a different capture card? Could always be that some capacitors in the TBC need replacing. Usually anything that is made worse by turning on the TBC is a TBC capacitor problem in my experience.

[joekalle]

ya, the line occurs on TV and capture card. It pops up as soon the TBC is turned on. Since it seems to fade away in certain colors i thought it might be a kind of distortion. But it´s confusing that it just seems TBC related.

[latreche34]

Keep in mind TBCs are half analog, half digital, For that problem to occur precisely at the exact same time of each scan line indicates there is an issue in the timing circuit of the digital section, A bad component is introducing noise at the HBI frequency into the actual video scan lines at the video output of the line TBC, Why at that precise location? It may have to do with the delay in time between when a scan line is read by the TBC and when it is output for display.

This is all my guessing, but I would find the service manual and look for that section and check for anything really, dry joint, bad cap, loose chip's pad, anything causing noise in the timing section, Sometimes gently tapping on a circuit board or a chip reveals something, Hot or cold air blown on a specific component also another way of troubleshooting this kind of problems.

[lordsmurf]

Welcome.

Note: caps = capacitors.

It's now gotten to the point where a non-recapped Panasonic S-VHS isn't worth troubleshooting until re-capped. So many issues are caps related, especially anything weird/odd.

Only a very specific issues tend to be non-caps related, most of those mechanical in nature. It's rarely the heads either.

Panasonic decks are some of the best decks ever made, in terms of addressing certain playback issues. But in general, they're some of the most frustrating miserable money-pit tools you'll ever own. So if you can avoid owning one, do. The JVC decks are vastly better for 90%+ of tapes. It's only that 1% to 10% that truly improves. Those Panasonics inject as many issues as they resolve, it's never "just better" than a comparable JVC, especially with luma values.

Panasonic S-VHS owners always get my nod of sympathy. I know your aggravation well. Good luck.

But it starts with a re-cap, you're mostly just goofing off until that done.