Need help with a projector: flat ferrite substitute for LCD module cable

[Koray]

Hi all!

I am refurbishing a projector (EPSON TW5300). There are tell-tale signs that it was previously repaired.

When I put it back together it works but the image has some random interference artefacts. I reseated the LCD ribbon cables, it worked once, but when I had to disassemble and reassemble the interference came back. It happens at different color channels in different shapes and I think it has something to do with the LCD ribbon cables.

When I looked at other people's TW5300 repair videos, I noticed that mine had no ferrite pieces around the LCD ribbon cables while others had thin flat ferrite bands. I assume at a previous repair mine were lost.

I don't think I can find anything that can fit there like the original, but I have an idea. Can I substitute a shielding metallic tape for a ferrite? I can encapsulate the shielding tape in capton tape and wrap it around the ribbons. Would that work?

See the photos of my projector's LCD ribbon cables, the shielding tape, and some blurry screenshots from the other people's repair videos.

Thanks in advance!

Koray

[thm_w]

It looks like it already has some level of copper shielding in the flat flex itself. Adding more might help, or might not do much. No harm to try a bit. It should be grounded.
If it worked once without the ferrites though that makes me suspicious that the problem is something else.

https://www.aliexpress.us/item/3256803568588508.html

[Koray]

Thank you for your suggestion!

I prepared a makeshift ferrite substitute with 4-5 layers of metallic shielding tape. I then wrapped the shielding with cloth tape for insulation. I applied the new shielding without removing the LCD ribbon cables so that I could test its functionality. IT WORKED! :-) Apparently the interference from the upper board (only 1cm away) was too great. See the photos below.

The image quality and contrast was still not to my standards so I tore the projector down again and this time I completely disassembled and cleaned the lens elements. They were all cloudy. Now like brand new and the contrast is much better. For anyone working on the optical block in projectors, I advice checking the projector lens for cloudiness, too. It also makes a difference. I had to clean and re-lubricate the auto-iris, too. I put it all back together and test run for an hour or so, works great!

A pleasure to post and receive messages in this forum! Thank you all!

Koray