Sanyo VTC5000 Patterning

[matsushi]

Hi, I have the following patterning on my VTC5000. Yesterday it worked fine and I did I played 1 tape twice and another tape once and the picture was good. (both L-750's)

I use a rewinder device to rewind the tapes.

Tape was removed. The videorecorder was turned off and unplugged overnight.

This morning I tried to play the second tape again and get this patterning. This same patterning appears on all tapes played now.

I haven't adjusted the tracking since yesterday and if I do it doesn't have much affect on the pattern.

Could this be the heads clogged or a hardware or an interference issue? leads appear ok.

This happend last year and I put the video recorder back on the shelf for 6 months and used it for the first time yesterday. (so it seemed to clear by leaving it on the shelf)

[dj_fivos_sak]

Look for bad solder joints on delay lines in the VD-1 board. This doesn't look like clogged or bad heads.

Fivos

[matsushi]

Thanks.

[ben]

check no routers, mobiles, etc. are nearby! Could be RF patterning I suppose, a bit hard to tell. Check internal earthing and shielding.

[mcousins]

That's jogged my memory... I remember some shielding/earthing issues with this model but it's so long ago... I think maybe it was the bottom cover. I recall fitting an earth link to one of the fixing screws, probably from one of the mains transformer fixings.

Regards - Mark

[toshiba tony]

Wasn't this caused by the metal cover on the bottom? Something rings a bell here.

[TIMTAPE]

Some Sanyos also had a metal plate above the video head area and below the PCB above it. If removed or maybe not grounded, interference could happen.

[dj_fivos_sak]

If it's indeed a drum/head disk grounding or head amp grounding issue, it might be fixed by connecting the upper drum and outer shield of the head pre-amp (VP-1) via a bodge wire, like I did on my VTC 5350 here: https://www.vintage-radio.net/forum/showthread.php?p=1293642
Apparently the head drum on these machines is self-grounded by the bearings of the lower drum's motor, and as the bearings wear, the grounding weakens. That's what I heard in a video by 12voltvids on YouTube.

Fivos

[matsushi]

Thanks have been reading your comments with interest. The grounding wire sounds like something I could try. but I do have intermittent success with playback and I now operate it with a fair amount of superstition to get good pictures (The sound is always good):

I avoid leaving it powered-on for more than 5 hours in a day.
If the picture goes to pot I leave it a couple of days or I put it back on the shelf ( stored sideways). Normally when I get it out after a week or so it works again.

For example today, I captured the start of the tape: 5 minutes of a gardening program. There was another program that had been recorded after it on a different occassion and that was looking like noise. I then rewound and the gardening program was equally unwatchable. I'm sure that if I try again at the weekend it could well be ok again.

[matsushi]

Hi, This VTC-5000 already has this earth connection on the top. see attached picture.

I haven't checked to see the bottom cover earthing but not sure what to check to verify it is earthing correctly. I'll post a picture if that helps?

I'm guessing the problem could likely the VD-1 board as you suggest. The Tracking has now to be wound fully round to the left in order to get a good picture.

[matsushi]

I went ahead and took a look under the base.

The earthing connection is immediately obvious and is intact. it is the smaller screw in the baseplate at the front and it screws from the base to the metal bracket you can see in one of the images.

I found an earphone cover an a 1p coin from 1994.

Have included photos of the board.

[matsushi]

the remaining pictures.

[matsushi]

I have another VTC-5000 which doesn't power up(just goes to Timer mode). Could I try directly swapping the VD-1 board? Is it just a case of plug and play?

[HamishBoxer]

Worth a try.

[G6ONEDave]

Might be a silly comment but have all the tapes that show patterning been rewound on the tape winder machine? If so try a tape that has not been, as it could be interference that's actually on the rewound tapes. Possibly having been caused by changing magnetic fields coming from the winding motor or a bad switch mode power supply.

Dave

[matsushi]

Originally Posted by G6ONEDave

Might be a silly comment but have all the tapes that show patterning been rewound on the tape winder machine? If so try a tape that has not been, as it could be interference that's actually on the rewound tapes. Possibly having been caused by changing magnetic fields coming from the winding motor or a bad switch mode power supply.

Dave

I didn't consider that. I will let you know how it goes.

[matsushi]

Hi, hope people are doing ok. happy new year etc...

I have had a mixed bag as the recorder is fine sometimes and others not. I have received some new tapes for my collection - The patterning seems to be always present but to a lesser or greater extent. I have attached some recent examples.

Interestingly if I upload a video to youtube when they process the video the pattern seems to disappear!

I maybe not discern what is normal Betamax quality and what is a problem with the VDC.

Plugging in a VHS player to the same equipment does not have the issue.

Your comments are always helpful to help me know what I am looking at.

THe first and last attachment are from the same tape as is the second. The third and fourth from a different tape. Bonus points if you guess the film/advert/series

[spamfritter]

Airwolf ?

[HamishBoxer]

How are you connecting this machine ? Through RF or Audio / Video inputs? Looks like RF patterning or RF Modulator (If used) off Tune.

[matsushi]

Originally Posted by spamfritter

Airwolf ?

Yes correct, they are:

Ferrero Rocher (the Ambasadors Ball)
For Your Eyes Only
Airwolf - The American Dream
Airwolf - The American Dream
Ferrero Rocher (the Ambasadors Ball)