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Actually I think my sets tend to pull the picture to the left on the top when I am watching a tape. I have never been able to figure out why they do this.
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I had that problem, and the problem turned out out be that VHS just sucks.
All kidding aside, what I found out is that there are a lot of time base variations. In other words, the time between sync pulses varies quite a lot. VHS (and most other things video) record diagonally across the tape in stripes. The "pieces" of recording have to be grafted back together. There are errors. When the tape starts to stretch, what was horrible gets even worse.
Our old sets were made for over the air broadcast, and the standards for broadcast were very strict. Probably they still are. Errors like what come off of VHS simply wouldnt be allowed. It was assumed that the broadcast signal would be stable and accurate. It was also asumed there would be some interference. If 2 or 3 sync pulses (and the video inbetween) were lost, It would be a lot less noticable if the set didnt lose sync. The horizontal oscillators were built with a "flywheel effect" to keep on going at exactly the same speed until the sync came back. In a picture, three lost pulses would just be 2 lines, not even next to each other because of the interlace, for half a frame.
Vintage sets usually display the crappy VHS signal just as it is, complete with all the timebase errors. Modern sets dont have the flywheel effect, and the horizontal frequency can vary quickly, following each pulse. Ironically, modern sets look better on VHS because they are more unstable.
I solved it by getting a JVC vcr with a built in timebase corrector. It fixes this completely on all but the worst tapes.
Welcome Adam
Frenchy: Have you looked at the horizontal oscillator waveform on a scope yet? I think on ctc10 thats how you adjust them. Anyway it might make it easier to find out what capacitor is toast.
John