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Old 01-23-2019, 03:22 AM   #1
Tom41
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Default Panasonic VCR horizontal line

I recently obtained a Panasonic NV-HD100 VCR that I was hoping to use to transfer VHS tapes to computer. While the mechanics of the loading and handling mechanism seem perfectly fine, there are a couple of small issues with the picture.

Firstly, there is a very fine noise pattern all over the image. It's possible however that it would have looked better on an old CRT TV and the modern HDTVs are just showing it up better. If I turn the sharpness control right down, the pattern is suppressed but of course then the image is very soft; not what I want.

The second, and slightly more serious issue is a horizontal noise line that's appearing on every tape I try. It's always in the same part of the image; roughly halfway down the screen. It looks rather like the 'sparkles' you used to get on analog satellite if the dish was very slightly misaligned.
You'd think if the heads were dirty, the noise would appear all over the screen but no, it's only in a certain part. A horizontal line usually means there's some kind of crease or other damage all the way down the tape, but I have inspected the tapes for damage (they are fine) and it's the same kind of noise on each different tape I try.

Could either of these problems be caused by bad/dry caps? Is it a sign of impending catastrophic failure? If that's the case maybe I shouldn't play old home movies or other irreplaceable tapes on it...
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Old 01-23-2019, 11:39 AM   #2
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Default Re: Panasonic VCR horizontal line

Does the line show up in the same place when playing SP or EP tapes? It is likely a bad cap but finding it could be a problem, If you have access to a scope that would help. It can be hard to trace the problem because of the seperate boards that plug into the main board are hard to access. It could also be caused by worn heads if the vcr has a lot of hours on it.
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Old 01-23-2019, 12:50 PM   #3
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Default Re: Panasonic VCR horizontal line

what is the source of the tapes in question? Have you tried the original machine? Perhaps the source machine had an issue which is latent in the tapes now. Also as asked about the "mode" of the original recording. EP doesn't give a very good "data source" for "archival" / source transfer.
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Old 01-26-2019, 01:49 PM   #4
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Default Re: Panasonic VCR horizontal line

Fixed horizontal line usually means a dirty lower drum,Give this a good clean.Particularly to the front-centre, as this is where your line is appearing. The other noise issue is most certainly dodgy caps in the psu-the noise usually fades as as the caps heat up,maybe after 30 mins of playing or so.Another possibility is a worn upper drum for noise artifacts,Head life was poor on these machines,mostly due to re-winding while still in the laced up position.
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Old 01-28-2019, 11:29 AM   #5
Tom41
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Default Re: Panasonic VCR horizontal line

Being in a PAL region, EP mode was never really an option with our VCRs. I tried to avoid LP mode as much as possible due to the quality degradation, and the vast majority of tapes I've tried have been in the SP mode. Regarding the original VCR that recorded the tapes, that was from 1988 and was thrown out many years ago. I have also seen the noise line on store-bought movie cassettes though, and they certainly wouldn't have been recorded by a defective machine!

The problem is extremely minor at the moment, and the VCR is certainly not showing any signs of mechanical problems. I'm actually reluctant to open this VCR up as I could cause more harm than good - particularly if the power supply is involved. As they say "If it ain't broke don't fix it". So I'm not going to do anything unless the noise line or pattern increases to an unbearable level.
I have also uploaded a picture to show what it looks like at present. It's much more apparent on a moving video when the line is jumping around, but you can't post videos as attachments on this forum.

I did have a VCR many years ago with bad caps; I had to let it warm up for 5 minutes before using otherwise it would play badly and mangle tapes!
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Last edited by Tom41; 01-28-2019 at 11:31 AM..
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Old 01-28-2019, 12:41 PM   #6
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Default Re: Panasonic VCR horizontal line

So the line is on ALL tapes that were recorded on another vcr? Have you tried a pre recorded tape (movie)?
Removig the cover to inspect the upper drum is not going to harm anything. It may very well be a piece of crap stuck in one of the groves of the drum assembly.
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