Problem with transcoder TVX - Television Experts

[ofesad]

Hi people! Ofesad here from Argentina!

Recently I got this transcoder, got it for 10usd, tested the composite output and works fine.
Brand it's "TVX television Experts" and in the back as a "made in USA" stamp.

If feature bars generator, Svideo in/out, transcode and a procamp.

[Attachment 58387 - Click to enlarge]

I tested the composite output and it works like a charm, however the Svideo seems to have some issues.

At the beginning I has having issues (noise) in the whites.

[Attachment 58388 - Click to enlarge]
(mostly when using a 25ft svideo cable)
This was solved by increasing a trim pot in the main board, probably gain?


However the issue that remains is in the top some sort of flickering. The same happens on any cable.

Video:
https://drive.google.com/file/d/1m_QNFplt3RikFTgYgc9X5wFGn8h2fuwb/view?usp=sharing

I already changed the only electrolitic cap on the main board, didnt have any effect.

Here some pics to see it:
MAIN BOARD

[Attachment 58389 - Click to enlarge]

FIFO

[Attachment 58390 - Click to enlarge]


[Attachment 58391 - Click to enlarge]


[Attachment 58392 - Click to enlarge]


[Attachment 58393 - Click to enlarge]

BTW some IC's have been sanded. The old practices so you cant know what they are.

Capture was made with a brand new Hauppauge USB-Live2 using Virtualdub2.

Any ideas are welcome!

Also, if anyone had or has this transcoder and has the manual, would be kind enough to scan it and upload it? I haven't found any information on this device whatsoever.

Thank you for reading!.

Ofesad

[jagabo]

The same happens on any cable.

Even a short (6ft or less) cable?

[ofesad]

The same happens on any cable.

Even a short (6ft or less) cable?

Yeah, even short cable (new old stock).
Try'd different ones and the problem remains.

I was thinking to change the svideo connector on the transcoder... I already clean it with isopropyl and contact cleaner. No difference.

Maybe the caps on the psu? but it delivers 4.99 ~ 4.98v quite stable.