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  1. I have the exact same problem as these threads.

    https://forum.videohelp.com/threads/347549-Screen-Tearing-TBC-Problems-on-JVC-HM-DH40000U

    https://forum.videohelp.com/threads/249734-JVC-Digital-TBC-and-Panasonic-ES10-filter-question

    My capture device is ADVC110. Is it really heat/fan related? The tearing only appears on some commercial and homemade tapes. The TBC also causes the audio to stutter.
    Last edited by digicube; 11th Sep 2016 at 21:31.
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    No TBC can overcome all timing problems. Sometimes you'll get a better picture with it turned off. Your audio symptom tells me you may need to adjust tracking, which could improve the picture as well.
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  3. The JVC TBCs generally straighten out decent sources and get rid of the 'wiggles' but tend to choke on poorer sources with flagging issues. I would love to explain it more technically but I can only speak from what I've seen. My experience has been that all released DVHS units have similar capabilities and performance. The only VCR TBC that takes almost everything with no issues is the AG1980. The late Panasonic DVD recorder TBC/frame sync capabilities work very well but can only do so much from an outside source.

    I would say that it has nothing to do with heat from what I've seen.

    If you are looking to get consistent LTBC straightening, you end up needed a Panasonic something somewhere in your capture chain. You can certainly get acceptable results without it but results may not be consistent. If you don't want to spend the extra money, you can potentially crop and resize at the cost of considerable quality loss.
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    Also known as skew error, it's related to stretching or shrinking of the tape. BOPET (the polyester base) is very strong and stable for its extreme thinness, but can shrink after a few decades, especially under poor storage conditions. This alters the geometry of the magnetic stripes so that the video heads can no longer track them all the way across. Some decks (principally U-matics) have skew controls that put higher tension on the tape in an effort to stretch it back into shape.
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  5. Is it really heat/fan related?
    Depends on exactly which JVC model. The 30000, 40000 and a couple other DVHS units definitely have heating issues due to poor internal airflow over their redundant A/D converters (that nobody actually uses for anything). The converters heat up the TBC chips and trigger problems. Later DVHS models either eliminate the redundant converters or have better cooling designs. None of the SVHS DigiPure models (like 7600) have similar heating issues.

    The tearing only appears on some commercial and homemade tapes.
    This is typical of all SVHS and DVHS vcrs that have inbuilt TBC/DNR. None of them are 100% consistent and perfect with every tape, every time. Even the famed Panasonic AG1980 will crap all over certain tapes when its TBC is engaged. Unplugging from AC to clear the chips occasionally does the trick, per robjv1 (who has owned many a JVC in his day).

    TBC/DNR is not the magic cure-all its made out to be in forum threads: its a useful tool, but doesn't always apply. When it works with your tape and encoder, its great, when it doesn't, its just a big PITA. The ugly flip side of many exotic VCRs is they suck a tailpipe when their precious TBC/DNR is turned off (you can get just as good or better playback from a $20 pawnshop vcr when that happens: a perverse irony that vexes many of us).
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