"Pulsating" top 1/3 of picture of VHS tape

[dr.pauli]

Some, not all, of my VHS tapes exibit a "pulsating" in the top 1/3 of the displayed picture. There is also a slight tearing effect on some of these tapes. The condition is visible whether or not the signal is fed through a macro-eliminator, so I have doubts that it is the copy protection. Since not all tapes show this problem, I have doubts that it is VCR related, though I suppose that it could be a tracking issue. The VCR in question has auto tracking (it's a JVC SVHS capable deck), so I don't know of a way to manually adjust it.

Does anyone have any ideas about what could be causing this and perhaps a recommendation as to what I could try to eliminate it? Thanx!

edit Wilbert: adjusted title a bit

[ejones]

You could try cleaning the heads......???

[bb]

Try to spin the whole tape back and forth. This may solve the problem (not guaranteed, though).

bb

[dr.pauli]

Thanks for the feedback, but I already done did both scenarios. Plus, I found out how to force the deck into manual tracking mode, which did not help either. :(

I did solve the problem, tho. I took my fancy-dancy, $200 JVC S-VHS 4 Head Hi-Fi VCR, with less than 100 hours usage on it out of "service". I replaced it with a $50 Sharp "close-out", open-box deck from Target, which came complete without owners manual and/or cables (but did have a remote), and all the problems disappeared!

I should have tried that first, but it didn't seem reasonable that it was the VCR since it was a "Good" unit with low mileage, and some tapes worked flawlessly. Oh well, you live and learn, albeit SLOWLY at times.

Thanks for the interest guys.

[Doobie]

Originally posted by dr.pauli I did solve the problem, tho. I took my fancy-dancy, $200 JVC S-VHS 4 Head Hi-Fi VCR, with less than 100 hours usage on it out of "service". I replaced it with a $50 Sharp "close-out", open-box deck from Target, which came complete without owners manual and/or cables (but did have a remote), and all the problems disappeared! [/B]

VCRs are a mature technology (all the key patents have expired), and given the public's abandonment of them, they're dirt cheap. Back about 5 years ago when I started getting intested in audio and video, I concluded that, with most electronics (don't be crass), you buy the cheapest (ignore brands) thing that has the features you want. Essentually, the cheapest 4-head hi-fi VCR is as good as the most expensive. And, if the most expensive is a little off, then the cheapest is better.

[jorel]

don't worry. your vcr need little mechanicals adjusts/repairs in the "posts"(stakes) and in the "tape tensor". excuse me but i don't remember the right names of that mechanicals parts...your technician will solve this problem easily,this is an simple and "basic" problem!
:)

[bb]

It's not true that it doesn't matter which VCR to buy as long as it's a four-head HiFi model. I have two of those, a Sanyo and a Sharp. The latter is clearly better in terms of picture quality: While you always get blurry video from the Sanyo not matter what you try, the output of the Sharp VCR is crisp and has better colours.

bb

[jorel]

true bb! the quality change from labels and models too!
some little details: no matter if the vcr have 2,3 or 4 video heads cos only 2 heads are working when we are playing or recording.
if the video have more than 2 heads,the remainders heads only work in "special effects" like pause,slow motion etc. if the video have 4 heads,2 heads work in SP,the others 2 in EP and the 4 heads in slow motion,pause ff with play,etc! the HI-FI heads are in the "cilinder" too but the vcr also rec and play the in the normal audio head(mono) to stay compatible with tapes from and for mono vcrs!
some vcrs have option to LP speed that use the same heads of EP(SLP)!

[dr.pauli]

Originally posted by jorel
don't worry. your vcr need little mechanicals adjusts/repairs in the "posts"(stakes) and in the "tape tensor". excuse me but i don't remember the right names of that mechanicals parts...your technician will solve this problem easily,this is an simple and "basic" problem!
:)

Hehe, probably true, but, the cost of a "basic" tweak by a technician in a shop somewhere will cost MORE than replacing the VCR. The last time I saw a service price qouted it was like $59.99 + parts., and that was > 5 years ago! If I stumble across a schmatic somewhere, I'll take it to work (where I have some test equipment) and do the "fix" myself. But, thanks for the feedback.

[Doobie]

Originally posted by bb
It's not true that it doesn't matter which VCR to buy as long as it's a four-head HiFi model. I have two of those, a Sanyo and a Sharp. The latter is clearly better in terms of picture quality: While you always get blurry video from the Sanyo not matter what you try, the output of the Sharp VCR is crisp and has better colours.

It could just as easily have been the other way around.

[SeeMoreDigital]

VCR's are quite interesting beasts!

At work we have several JVC (S-VHS) machines. All were bought at the same time. All are the same model.....

And some of them can produce quite different looking images from the same tape!

I guess some were made on a Monday and some on a Friday :D


Cheers