Strange rolling tracking problem?

confusedperson · #1 05-19-2019, 06:49 PM

I have this problem with my best VCR and it's driving me up the wall.

With some tapes, if they are at EP speed and near the beginning, the tracking will just suddenly roll itself rapidly. At this point I have to eject the tape and insert it again, where it will play for another minute or so before rolling once more. Switching to manual tracking does not prevent the issue. The worst thing I can do at this point is stop the tape and immediately play it again, as this causes the EP tape to play at SP speed, damaging the tape itself. So....there are tapes I have had to digitize one minute at a time.

The problem only happens at the beginning. Depending on the tape the issue will last from one to two hours in. A tape that rolls at the beginning will usually not give me trouble if I start playing it one-third of the way through.

It does not do this with every tape. Only specific ones, and it is not clear AT ALL which ones it will do it with. If I eject a rolling tape and put in one I know doesn't roll, it plays normally, but if I put the rolling tape back in, after a couple minutes it starts rolling.

This problem has me completely stumped. What could be causing it?

-- update --

Okay, now it's doing it with every tape and it's having the rolling problem later in its run as well. Eventually it won't be able to play any part of any tape at all, which will be a true tragedy, as it's very good for digitizing. Every other VCR I have is worse.

lordsmurf · #2 06-26-2019, 11:11 PM

I've seen tapes where the recording data was malformed, and it will roll, or even chipmunk (play too fast) or the inverse (play too slow), and you have to constantly baby the VCR. When it acts up, stop, maybe eject, record the next segment for as long as you can. Repeat.

We're having the problem with a client tape right now. Frustrating.

confusedperson · #3 06-27-2019, 12:35 AM

Quote:

Originally Posted by lordsmurf

I've seen tapes where the recording data was malformed, and it will roll, or even chipmunk (play too fast, or the inverse (play too slow), and you have to constantly baby the VCR. When it acts up, stop, maybe eject, record the next segment for as long as you can. Repeat.

We're having the problem with a client tape right now. Frustrating.

I have also had to do that, but with so many tapes to go, it's kind of a luxury I can't afford to waste time with.

I have no doubt that at least part of the problem is the tapes, because my dad had this really strange VCR for many years. It was very high-end for its time, with many buttons. It was VERTICALLY oriented, so you stuck the tapes in sideways. Only VCR I've ever seen that worked that way. You can see it in an old home movie of mine. I've always wanted this model identified...does it look familiar?

I'm convinced that this vertical design, combined with gravity, is what eventually made the machine slip out of alignment and tape everything with screwy tracking. I've had problems with the tapes recorded on that thing that I have NEVER had with stuff taped on any other machine. And, unfortunately, he exclusively used it from 1988 through 1997.

BUT I put a tape of my own making into the D-VHS today and after a minute it began rolling. So now I don't know what to think.

hodgey · #4 06-27-2019, 10:24 AM

Does it happen on all vcrs, or just this one? If it's the VCR, one thing you can try is to seat/unseat and clean the ribbon cable or cable connectors that connect the Audio/Control head to the VCR (and make sure the head itself is clean). Afterwards, try check it for continuity with a multimeter.

AC_HEAD.jpg

If you happen to have access to a oscilloscope you could also check if the player sees a tracking signal, but scopes are not something most people have lying around.

It is possible to adjust the A/C head height and tilt to, but it's not normally something that get's out of position by itself (as opposed to tape guides). So if you have a set of tapes with a misaligned control track that is a possibility if you have a "sacrificial" vcr you don't mind messing with, but not sure how likely it is to work.

As for the VCR, a quick search led me to this
. (Image attached since ebay auctions disappear.) Could that be it? I believe JVC has also made a vertical VCR, but that was newer and silver colored I think.

confusedperson · #5 09-11-2019, 12:17 AM

The problem has gotten far worse; the tracking now rolls on everything, including SP tapes (that never happened before). It also does it no matter where the tape position is -- beginning or end. I'm officially declaring this VCR dead unless anybody has any brilliant ideas. It's a real tragedy -- it rescued some pretty bad tapes from the brink; it was great for that.

To the above poster, the ribbon cable is pretty tightly connected; I doubt it's that.

latreche34 · #6 09-11-2019, 12:55 AM

Clean the heads pictured in post 4.

hodgey · #7 09-11-2019, 05:41 AM

Rolling would indicate that there is an issue with the control track signal. It could be simply the head being clogged, bad contact somewhere, or a bad component. It's hard to tell exactly without being able to measure the signal path.

dpalomaki · #8 09-11-2019, 08:32 AM

Head or mount might even be a bit loose and shifting position slowly.

What model Zenith is the VCR, VRD230?

I see one on EBay for a rather high price!

confusedperson · #9 09-12-2019, 02:32 AM

Tried cleaning it again....problem remains.

Quote:

Originally Posted by dpalomaki

Head or mount might even be a bit loose and shifting position slowly.

What model Zenith is the VCR, VRD230?

I see one on EBay for a rather high price!

It's not a Zenith, it's a JVC D-VHS 30000U. Can't be the head or mount or I'd notice when I took the cover off, right? Or they'd be making a noise?

There is ONE repairman in this city who looks at VCRs, he IS familiar with this machine....and he wants about $300 just to look at it.

latreche34 · #10 09-12-2019, 02:25 PM

Possibly an auto tracking circuit failure, so you will be looking at bad capacitors or circuit protection resistors which means a service manual and tools, If you are not comfortable doing it cut your losses and move on.

confusedperson · #11 09-12-2019, 04:39 PM

Quote:

Originally Posted by latreche34

Possibly an auto tracking circuit failure, so you will be looking at bad capacitors or circuit protection resistors which means a service manual and tools, If you are not comfortable doing it cut your losses and move on.

There's a twist here too -- I took the power supply out a few months ago and had it checked out. They said the capacitors all looked fine.