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aramkolt 03-13-2024 09:08 PM

Possible video artifacts on TBC-1000?
 
1 Attachment(s)
Hello all, I finally got a hold of a TBC-1000 to do some testing against rack mount TBCs and I am wondering if this is glitch anyone has seen before - see attached video. This is zoomed way into the top edge of the picture.

Basically what happens is there's some rainbow static up in the vertical blanking area that would normally be all black. The closed captioning area right above the picture also seems to jump around a lot more than I am used to seeing from other TBCs.

The rainbow static is kind of unpredictable and it'll only do that very once in a while.

The rest of the actual picture looks fine.

I have not done any recapping to this unit, but would like to know if this is something commonly seen that is usually fixed by recapping, or if there's likely something more seriously wrong going on?

lordsmurf 03-14-2024 08:28 AM

It's literally now gotten to the point where any non-refurb'd DataVideo TBC is suspect, bad caps are rampant, even failed chips and power. I acquired** multiple units in the past year, and more than half (50%+) of the units were bad. All of them, of course, were "working great" according to the previous (moron, liar) owner.

** Note This excludes any dealing on-forum. I refer only to off-forum dealings here, not members here.

I'm not able to look at your sample now, but will in a bit. I'll only reply again if I see anything normal, anything that doesn't suggest unit damage.

Cypress has avoided this fate, which is why I focus on locating those units for our community, as found in my marketplace listings.

aramkolt 03-15-2024 07:04 PM

It's odd because the static only appears in the vertical blanking area and it is not consistent. Once the unit is warm, it seems to do it less, or it might just be totally random and I haven't noticed it. Doesn't seem to affect that actually normally viewable area that you'd capture with a capture card, so I don't know if many people actually look above the picture using a display that can do it with something like "pulse cross".

The very top line sometimes likes to scroll.

I plan to do a full recap of the unit if I decide to keep it and also bypass the distribution amplifier, but I was hoping someone with experience with these said that they'd seen this problem and that it went away after a recap.

Issue seems to be that most people probably can't see their vertical blanking area to know if theirs is doing this as well.

I'll post some actual captures using a regular capture card in a bit to see if anyone can see actual picture deficits in the viewable area that I'm missing.

lordsmurf 03-15-2024 07:14 PM

Forgot to check that last night, busy.

I'm not entirely sure what I'm looking at. It looks like an iPhone taking a video of a monitor.

Are you PAL or NTSC?

aramkolt 03-16-2024 10:37 AM

1 Attachment(s)
Yeah, it's an NTSC playback of Rocky II from a 9900U - did that whether the line TBC is on or not. It actually doesn't have macrovision encoding on it as I guess it must have been one of the earlier releases. It's plugged into a VTM Series professional monitor via composite - that has built in waveform/vectorscope functions and allows you to see the full frame including the blanking area - it was indeed a phone video of that screen. If I were to capture with a traditional capture card, the vertical blanking area wouldn't be a part of the capture and you wouldn't see those artifacts to know anything is wrong as the picture itself seems fine.

My original hesitation about going ahead and opening to recap was that I could return the unit as it's not working, but if I opened the unit to actually check anything inside, it would no longer be returnable due to anti-tamper seals, so I was curious if this was a commonly seen issue prior to recapping. Curiosity got the best of me and I ended up breaking the seal, so I can't return it now haha.

Sooooo while the caps were mostly testing good in-circuit, only 4 out of the 25 or so were actually good out of circuit on the TBC100 board. One tested as high ESR but also "leaky" so that could have been some of the signal contamination maybe. I'm pretty confident that new caps will fix it. I've already done the recapping and I'm just figuring out exactly how I want to do the bypass mod before re-assembling to test that the issue went away.

While others have said - you should assume that you'll need to recap the TBC-100 as those Wendel Caps are absolute crap. Based on the refurbishing videos I'd seen, I assumed some would be bad, but not for 75% of them to be bad.

If your TBC-1000 functions well now and hasn't been recapped, I'd suggest recapping it now since you never know when these video artifacts will pop up and you're not going to want to repeat captures when they eventually do show up.

Attachment 17620

lordsmurf 03-16-2024 12:09 PM

NTSC? Interesting. This is something you'd normally see with PAL, especially the NTSC-first units processing PAL.

I think a lot of people would be surprised where Macrovision shows up. For example, smaller run cartoons like The Tick and Cartoon Network compilations have nasty anti-copy. The Young Indiana Jones Chronicles are awful too. But then you get a "big name" movie and nothing exists there.

Hahaha, breaking the seal! Oh no! Cue Sheldon on an early TBBT episode, the opening scene, the one where they rode the train and little miss Terminator was on board.

I want to get with somebody here soon to make a mod kit of these old TBCs. No matter how you bypass, I think it's all craptastic in the end. We can do better.

aramkolt 03-16-2024 02:51 PM

I bought a sealed VHS copy of Young Indiana Jones (for $7 shipped) for my eventual grand TBC comparison as I had heard the same about its macrovision. Gonna break the seal on that too :laugh:

lordsmurf 03-16-2024 03:25 PM

Quote:

Originally Posted by aramkolt (Post 95506)
I bought a sealed VHS copy of Young Indiana Jones (for $7 shipped) for my eventual grand TBC comparison as I had heard the same about its macrovision. Gonna break the seal on that too :laugh:

Just be aware that these vary. I have several copies, but only 2 have the anti-copy, and only 1 is really bad. I think the issue here is the quality of the contact duplication, and any offset caused issues. And then differences in batch runs. So it can be hit-or-miss for the worst anti-copy errors. It was common, but not easy to repeat simply by knowing the title.


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