3/4" U-matic Tracking Issues

Trevor's picture
Last seen: 1 month 3 weeks ago
Joined: 08/27/2012 - 6:33pm

I'm transferring a 3/4" U-matic tape right now, and I've run into a unique situation.
The tape contains a studio program, plus commercials. The commercials on the tape play fine, however the studio portions have considerable tracking issues; so much that the image is constantly jumping up and down. Now then running the signal through a TBC does alleviate quite a bit of the jumping, but the by the time the signal gets to my analog-to-digital converter, the picture is way out of synch with the audio and the converter puts out an audio signal that sounds like a CD that skips.
My setup is U-matic VTR to Hotronic AP41 TBC to ADVC-700, with the audio running right from the VTR to the 700 by XLR.
I've tried the tracking and skew on the VTR and neither have much effect. I've also tested other tapes, and the tapes play perfectly fine.
I've made 2 captures, and I've been trying to synch up the good audio from the one capture, and the good video from the other, but it keeps going out of synch. I will get a portion in synch, but then 5 minutes later it's massively out of synch.


paulears's picture
Last seen: 1 day 9 hours ago
Joined: 11/05/2006 - 8:36am

Sounds like the studio machine was out of alignment and the transfer to the editing machine was only just in tollerance, but now the errors are too great for the replay machine. and the originals are too far out. Realistically, do you have the kit and knowledge to realign the replay machine - probably skew and switchiung times just too far out. You'll have to spoil your machines alignment to try to recover the old one.


Trevor's picture
Last seen: 1 month 3 weeks ago
Joined: 08/27/2012 - 6:33pm

I didn’t realign the machine.  But what I did do was cut up the individual sections of the good video and export them as a separate files, and then I imported the files and adjusted the speed and duration of each file so that it matched with the audio.  For the most part the lip movements are in synch, but there are a few words, especially right around the commercial breaks where a word or two doesn’t quit synch.  


paulears's picture
Last seen: 1 day 9 hours ago
Joined: 11/05/2006 - 8:36am

No - what I meant was that if the commercials play nicely and the programmes don't then the tape is not first generation, and at some point material from one VT has been recorded onto another - and at this point the sync pulses have probably suffered, and now on the replay machine there's a bit more poor alignment so the already damaged sync is below threshold, but the only slightly bad content still plays. You may be able to find the happy medium if you are able to carry out realignment. It's actually unusual for the audio/video alignment to be wrong, that sounds more like something that happened at the digitisation stage when the sync got lost, so I think the cure is a physical one - adjust the alignment of the player.


Trevor's picture
Last seen: 1 month 3 weeks ago
Joined: 08/27/2012 - 6:33pm

I’m aware of that (since that is where I noticed the loss, was at the digitization stage.  And while I do know how to manually clean and do a few other mechanical tricks, when it comes to making sure that everything electronic works and is in alignment, I leave that to the experts, as I am not an electronics engineer.  

 

But it what I did seemed to work just fine.