Metz 9877 artifacts?

[cdg123]

Firstly Happy New Year to everyone.

I have been wanting to convert my VHS-C & VHS video tapes for many years to digital format but never managed to find the time which I have now and so spent many hours reading through the forum to understand the best approach.

I tracked down a Metz 9877 which I understand is a Panasonic NV-HS 1000 underneath however a bit dissapointed with the noise / interference I am seeing on it during playback so hoping you can offer me some troubleshooting advice.

The problem I am seeing is random white lines (see image attached) during playback.

To try and troubleshoot the setup I hooked up my original JVC VHS player (HR-J770) via the AV SCART on the Metz and I don't see the problem so is it possibly video head related on the Metz as I assume it is taking the signal in from the SCART AV socket processing it before sending it out on Composite and hence the electronics for that are ok?

I am capturing on a windows 10 machine via a new USB-Live 2 using the composite output of the Metz.

I believe I have eliminated it being a poor video tape as tested this using a commercial VHS recording of the events of 1964 plus tried my originals recorded in the JVC machine and the Metz is showing the same problem.

So any ideas to help trace and resolve would be much appreciated.

Thanks in advance.

[hodgey]

Yeah it's essentially a NV-HS1000, I don't know which revision.

The white line you are seeing is a dropout - the VCR isn't picking up any video signal from the tape at that point. Now it's normal for there to be dropouts on tapes, which is why VCRs have drop-out compensation circuitry. On modern VCRs this works by inserting a delayed video signal (i.e the previous line of video) if the VCR detects a drop-out. We've got an NV-HS1000 here, and my experience with it is that the drop-out compensation doesn't work well on it, leading to white streaks where another VCR like your JVC would mask the dropout. If you look closely at frames from recording from the JVC, you may be able to spot the dropouts.

I have yet to find out whether if this is due to a design flaw, or if there are some components that are not working well. Panasonics of this vintage are known for having electrolytic capacitors that go bad which can cause all sorts of issues, though the NV-HS1000 does't seem to affected otherwise compared to say the NV-FS200 and related models.

Now this can also be made worse by worn and/or dirty video heads which gives the heads trouble with reading the video signal off the tape. The heads on our NV-HS1000 seems to get clogged really easily, don't know if it's due to wear or something else.

The VCR doesn't do any processing on the input signal other than separating luma/chroma if you go from composite input to S-Video output. The TBC board is hooked up to the output signal from the tape, but not the external inputs, and this machine doesn't have any advanced digital filters like the JVC SVHS decks and the american Panasonic AG1980P. You should always be using S-Video out if available.

Last note, it's possible for white lines to be caused by bad contact between the carbon brush on top of the video head drum and the drum itself which result in static electricity buildup, but it doesn't look like that's the issue here. In any case that can be cleaned easily.

[cdg123]

Ah that makes sense so giving the heads a clean would be worth an attempt first then it seems.

Is there a best practice way to do this as I appreciate they are quite sensitive and not something easy to get replacements for?