Time Base Corrector Discussion 

Can we just take a moment and appreciate how amazing this technology is and the fact that it even works at all...

Black Burst is the signal that feeds genlock inputs throughout a facility. It's a normal video signal that's just black.

Its so nice we have full 4fsc frame sofware defined TBC today thanks to ld-decode and vhs-decode, with FM RF capture and preservation uprooting a market of inflation and outright missinformation.

Excellent video. Thanks for covering this.

Vblank is probably vertical blanking - in other words that'll remove macrovision if turned on. RF in is used for dropout compensation and gets the RF signal directly from the video heads and that's how it knows when there's a signal drop to then compensate for it, most likely by replaying the line from the prior matching field or the line right above it. Usually there's a DOC sensitivity potentiometer as well that'll tell the unit at what level of RF signal is considered low enough to be considered a dropout. I haven't ever heard of anyone adding a DOC BNC to a consumer VCR, but it should be theoretically possible since it's most likely just an RF tap to the RF test point with a capacitor in series.

Thank you for the information

Good morning, gummyroach. it is pretty vibrant video. thanks. :)

i think the bending of the top of the image is caused by creasing or crinkling the top or bottom of the tape. during the 2000s the last gasp vcrs was notorious for creasing the top or bottom of the tape because i guess the guides was slightly mis aligned and would cause the tape to be folded against the top and bottom plates on the analog audio/control head or did not sit on the groove on the bottom of the drum body.

Hi, does this is full tbc, since frame and field tbc seems like different devices and some do both functionality etc

thanks ,nice info !! i have one ,just learning

You should have explained line TBC and frame TBC separately, They have different functions, It's more technical than what you can explain to the average person unfortunately.

Had issues with vhs but never on beta or video 8. I thought it might be macrovision related.

I use to make capture with help of Pixel View low budget TV card, no problems what you have.

The IVT-7 can be good in theory, but often is not. Far too often, these are abused, and yours appears to be no different. The signal gets wonky, and must be recalibrated, using the screws that you rightly mentioned should not be touched. All of the controls on these units are touchy, and it's hard to adjust. The now-noisy bad-bearing fan often needs to be removed. Heat is not a problem since you're unlikely to run this 24/7 as designed. Modding to remove the fan requires partial dismantling the unit, and isn't fun. This TBC is a large "pizza box" type unit, wider and longer than VCRs, with sharp corners and edges, so it will own any desk or cabinet where used. In general, I don't suggest these to casual or new users. You rarely see these units in decent shape, usually only as "parts only", again due to typical abuse from broadcast facilities.

could you please add subtitles..

Thanks for making this video. Very clear and informative. I’d love to know more about the old YC cable. It’s not a DUB connector? Also, do you have any idea what could be causing this psychedelic pattern to emit from my VCR: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-S8YW-celr1U.html

i may be able to scan a manual for ya!