TBC control? Proper way to rewind a S/VHS-C tape

[Carlos Menem]

I think I'm breaking my camcorder using it to supposely caliber the tension of the tape by rewinding then forwarding and rewind each time I want to transfer some tape. I also have to rewind the tape using the camcorder "to keep tensions stable I suppose"; each time I want to redo a not so good transfer.

Is it possible to use the VHS adapter to rewind it on my VCR or can I use a standard rewinder will that cause tensions again is it safe?
If I can use a rewinder what type? What usually cause timebase problems... manual rewinder?
When I played this VHS-C on my VCR using the adapter, it it causes distorted images at certain points on the DV capture.

[jm1647]

I've always used a standalone rewinder to do my standard size VHS and VHS-C tapes with no problems tension wise that I can detect. They usually record again ok after rewinding.

[Carlos Menem]

I've always used a standalone rewinder to do my standard size VHS and VHS-C tapes with no problems tension wise that I can detect. They usually record again ok after rewinding.

My standalone rewinder causes timebase problems as it makes noise... it seems the tape doesn't caught up well with rollers.

[RFBurns]

Worn out tape guides on both the VCR units and stand alone rewinders will cause tape edge damage, which in turn causes the tape to "walk" up and down inside the guides when playing or recording, and that in turn makes the "control track" that keeps the machine tracking peaked, go nuts and you get bad picture, loss of hi-fi tracks, just general unwanted garbage.

Dirty tape guides will also cause this problem with playback and recording. Check those for buildup of tape particles that gather over time and make the tape walk off of the guide. The best way to determine tape walk is to examine the tape as it travels past the pinch roller and capstan shaft. If the tape looks like it is warping and not traveling smooth between the pinch roller/capstan shaft and the exit guide just byond that, chances are the guides in front of the pinch roller/capstan shaft (the one near the video drum on the exit side) are either worn out or have build up at the top and bottom guide hats. Clean as needed.

[RFBurns]

TBC is short for Time Base Correction, a pulse used in video tape media and machines in order to correct sync and color timing errors. More commonly found in video production and broadcast studio facilities, TBC's do a very good job in fixing up bad sync on video tape media. However TBC's cannot fix everything unless you are fortunate enough to afford the extremely expensive TBC's meant for broadcast and production facilities. A TBC requires GenLock, or "house sync" as us engineers refer it to. This "house sync" is usually a black video signal with the correct sync pulses and color pulse so that all of the video machines and other equipment like the video/audio routers and switchers can switch between video and audio sources without loosing the time base of each video/audio source. The result is a smooth transistion between the sources.

The TBC found in consumer gear is basically similar to the expensive big brother units, except the TBC does not use a reference house sync pulse. It generates new sync based on its count of the exsisting sync pulses on the media, and calculates the correct timing delay and color timing and re-assembles it with the new generated sync.

[Carlos Menem]

So do you mean comsumer TBC can still cause UNSYNC just not much image distortion?

Do you think a bad rewinder can cause timebase problems? I'm not gonna use my VCR/CAMCORDERs for the rewinding as I think they may broke sooner if I do. But on some forum I heard is a good idea to do just that so that it put a good tension on the tape? Que hago? What should I do? I don't believe my old rewinder... I bought a KINYO one says it also clean the tape too I may need advice on this soon too.

You think my new rewinder can cause timebase problems? If so, does this mean I always have to rewind the tapes on the VCR whenever I found them?

[RFBurns]

Its possible that a rewinder that has worn out guides or pulls the tape too hard or the hub brakes kick in at the incorrect time or they keep too much tension on the wind process can cause "tape strech", where the tape is pulled and changes width. It only takes just a fraction of strech to muck up a tape, any tape be it audio or video.

What the other forum was refering to is "unpacking" a tape. It usually is done when a tape has sat for a good period of time to loosen up the tape before running it through a machine. A stand alone rewinder is best for this operation. But unpacking a recent tape that has been used frequently is not recommended, only on tapes that have been sitting for a long time, years for example.

When a tape is streched, it not only changes the width and the position the tape rides along the guides and across the control track head, it makes the control track pulses change frequency because of the dopler effect. You can experiment with this by taking some old cassette tape, strech it just a bit in one spot, play it and listen to how the pitch changes in the music as it comes across the streched part of the tape. With video, it messes up the control track pulses and the video drum sync and make the picture loose tracking. In digital recordings you will end up with pixilization or freezing video.

[toomanycats]

When I had my repair shop I used to fix a lot of VCR's. Most of the problems were mechanical. Stand alone rewinders are crap. I have never seen one that could match the VCR. RFBurns is right, I would also check the head of the VCR and make sure it is still shines. You may have "stiction". Also make sure the tension arms move freely. Sony's used top freeze up a lot rendering an excellent VCR useless. You would be better using an old VCR for winding and rewinding the tape. Do not do it in Fast forward mode as the tape is pulled out and rubbing against the head. Most of the tape problems I have seen from stand alone rewinding machines was that they wound the tape too tight.

[Carlos Menem]

So you're all saying my new KINYO will still cause timebase errors? I have one tape that is giving me more timebase problems then any other... I fix it by forwarding and rewinding all... but if I put it on another vcr or rewind it on the standalone rewinder it will mess the video again. Should I Humid it? Can anyone tell me steps how to humid properly? or should I encase it on a new case? when I was little I did that on a tape case that broke.

[toomanycats]

It sounds like the recording head on the VCR is shot, it may be causing stiction (not shiny anymore) or it is dirty. This seems to be the case as rewinding then fast forwarding is changing the problem. If it is only happening on one tape, throw that tape away.

[Carlos Menem]

It sounds like the recording head on the VCR is shot, it may be causing stiction (not shiny anymore) or it is dirty. This seems to be the case as rewinding then fast forwarding is changing the problem. If it is only happening on one tape, throw that tape away.

But if is only with this tape why could the vcr head be stictioned? I already captured this tape successfully without color jumps after many retries... but I need to re-transfer it again because I recorded the audio in mono and I want stereo that gives me clicky noise but I will humid it and see what happens. So any advice for humidity?
Or what anti-stictionism tape should I use for the head?

[RFBurns]

The video/audio head elements may be intermittent. They are very fragile and can be damaged if cleaned incorrectly or get damaged tapes run across them on a regular basis.

Basically they are tiny coils with ferrite elements in the center of the coil. The ends are very shiny, machined to be smooth and semi-curved ).

Never use up/down motion to clean them! That will damage them instantly.

The heads might be worn that the "tip" penetration is behind the spec. At that point its time to replace the entire drum.

I hope you get all that going! Have a Happy New Year!

To all, a Happy New Year!!! See ya in 2007!!!