sinus wave movement artefact

[fabweb]

I have the problem of having this sinus wave movement in some of my Hi8 tapes.

The problem is that I cannot recreate this artefact in the same frame.
So it appears random. So I figured it is not on the tape.

The cables are fine too. I checked and replaced thme several times without success.

It seems that some tapes are worse than others, but it is not limited to one tape.

I unpluged the speakers and all non essential power appliances nearby, but I cannot rule out that this might be elictricity related.

Maybe a ground loop problem? I have no sound destortion when this proplem appears.

Could this be solved by more expensive cables and better shielding?

Capture setup:
10 year old Hi8 tapes played on a Sony EVS 9000E PAL
connected with a 1 meter S-Video cable to my DV camera acting as a pass through AD converter.

Just before:


with the problem:

[fabweb]

I put the tape in a D8 Camcorder and it got worse.
A lot worse!
It was no sublte wave distortion anymore but a big and anoying one. On top of that you could hear the tape squeel.

So I assume the tape is old and defect and the EVS made an incredibly good job in reducing this error while the Sony D8 did not help at all.

Problem solved.