Can the AVT-8710 be serviced?

[jdmack]

I have 2 AVT-8710 TBCs. They are both black, but they both worked fine for a long time. And then both of them (at different times) developed the same problem. If a video is somewhat overexposed, the AVT-8710 will make the image very overexposed. Is there anyone who can service these units, assuming that this is a fixable problem? Is there a service manual anywhere that can be downloaded?

[lingyi]

Post at digitalfaq.com and contact lordsmurf. He may be able to diagnose your issues and possibly provide help in repair, I think he's repaired some of his own units.

[dellsam34]

Use the keypad to lower the level of brightness, Most if not all TBC's affect levels when used, that's why you only use them when you need them.

[infjmm03]

I have 2 AVT-8710 TBCs. They are both black, but they both worked fine for a long time. And then both of them (at different times) developed the same problem. If a video is somewhat overexposed, the AVT-8710 will make the image very overexposed. Is there anyone who can service these units, assuming that this is a fixable problem? Is there a service manual anywhere that can be downloaded?

Of course the unit is serviceable, why wouldn't it be? Any electronics technician who specializes in video equipment repair jobs can handle that kind of job. Lordsmurf is NOT an electronics technician.

[lingyi]

Of course the unit is serviceable, why wouldn't it be? Any electronics technician who specializes in video equipment repair jobs can handle that kind of job. Lordsmurf is NOT an electronics technician.

An electronics technician may be better able to read and understand the schematics of the device, but they still have to know and understand what those components do and how they interact. They would also have to know [how] to source or find the equivalent part for replacement.

In 1981, when I got my my first Betamax, I met the Sony repair techs who were all electronics technicians and they said only the top audio techs who passed extensive VCR repair training where allowed to work on the then new Betamax machines. Over the next ~15 years, I saw only one or two new techs.

Also, don't dismiss lordsmurf's background and knowledge, he may well have a electronics technician background. He knows about and has done a lot more than he talks about in general here and at Digitalfaq. He recently unveiled that he learned to repair and refurb AG-1980's by himself and taught Deter, considered to be one of the best, if not the best person for repairs/refurbs, how to do the same.

[dellsam34]

I have a black unit and the default settings are not right, you have to lower them just to get the IN signal and OUT signal about the same, No need to mess with the electronics. If you got a pretty bad tape with overblown levels the TBC cannot fix that, it's baked in the tape.

[lordsmurf]

I have 2 AVT-8710 TBCs. They are both black, but they both worked fine

Those never worked properly. The black model chipsets are defective. You were just missing the problems ... until now. That's very common, and the reason black AVT-8710s are still resold (gullible newbies, unobservant users, inattentive users, etc). Condolences on your unfavorable discovery, but now you know what and why.

Only the green units are good.

Read this: http://www.digitalFAQ.com/forum/vcr-repair/3053-avt-8710-doa.html

Is there a service manual anywhere that can be downloaded?

No such manual exists.

Of course the unit is serviceable,

No.

why wouldn't it be?

Secrecy. In the 90s and 00s, TBC makers did all they could to lock and deface components. Some ICs can be swapped, some not. Hacking -- actual hacking -- is required to even attempt any meaningful servicing.

Any electronics technician who specializes in video equipment repair jobs can handle that kind of job.

No.

Lordsmurf is NOT an electronics technician.

And yet, an electronics technician wouldn't necessarily know his ass from his elbow in terms of what is the expected performance of a TBC. While I may not be an EE, I do know an incredible amount about TBCs, especially this exact TBC, and that does include chip-level information. Just FYI, in decades past, I had programmed ASICs/etc, reverse-engineered/written firmware, etc. I'm not some low-level low-brow user. In fact, about 20 years ago -- and it happened twice, with two very different video/media areas, and within a year of each other -- I wrote code that was considered "impossible". ("Impossible" was the community consensus -- and I was scoffed at when I told others of my work, and then again after it had succeeded. Trolls/a-holes being online isn't anything new.)

I have a black unit and the default settings are not right,

The AVT-8710s, including some green units, can have different gamma profiles.

He knows about and has done a lot more than he talks about in general here and at Digitalfaq. He recently unveiled that he learned to repair and refurb AG-1980's by himself and taught Deter, considered to be one of the best, if not the best person for repairs/refurbs, how to do the same.

That's exactly it.

For example, for most of the past year, I've actually been working with an EE to try and turn the black units into "green" units. But so far, its a step forward, then a step back. This isn't something just anybody can do, nor is it anything a person can do alone. TBCs are complex, regardless of what you may read in certain places, from certain people, about it being "a chip" (laughably not true whatsoever).

BTW, that sort of R&D takes investment, too. While I could quickly sell those "extra" TBCs for some quick cash, I'm instead risking my units for the greater good. A few members at the digitalFAQ.com forum have also donated to the effort, with more donor units. Plus time required, plus experience required. (Which is why I get somewhat miffed at certain mouthy folks on some sites. Talk is cheap. Effort and risk is required for actual progress.)

There are also things I do, for/with video/media, that I cannot even talk about, because of NDAs.

Another BTW, deter learned a lot past what knowledge I was able to bestow on him, and I think it's great, I'm quite happy that he advanced his skills as much as he has. My knowledge on AG-1980 came from Jots just before he retired, and a curmudgeonly media tech at a local college a few years before he retired, both about 15 years ago. We've entered a video phase where knowledge is passed, not formally leaned.

Post at digitalfaq.com and contact lordsmurf. He may be able to diagnose your issues and possibly provide help in repair, I think he's repaired some of his own units.

Yep. For any further commentary, questions, that's where you can reach me best/fastest.

[lingyi]

Two big pats on the back to you lordsmurf for speaking out about some of your accomplishments! Thank You!

I always get a chuckle when I bring up your name and advice, and someone says "How does he know, has he tried X?", and the answer is either "Yes", or he's explained in detail, usually backed by the other knowledgeable and experienced regulars about where and why "X" falls short.