TV RGB mod thread

[doofy77]

So, I attempted to mod my LG CA-21D33EX today, and was mostly successful, but the OSD Menu is now really dark.




The OSD menu isn't completely black, just very dark and faint


The AV2 is basically black


This set has the MC-84A chassis. I followed the guide here: viewtopic.php?t=60010. I Installed the missing resistor at R557 with 510R, I also had a missing resistor at R234 75R which i installed as well. Instead of bridging J99, I installed a switch so I could switch back and forth between CVBS and RGB. I managed to change the required settings in the service menu but it was pretty difficult to see.



Everything seems to work fine. I can switch between composite and RGB no problem but the OSD menu is almost unreadable.
It isn't just on the AV1 input though, it's on the tuner and on AV2.

Does anyone know what the issue could be?

It looks like the OSD is muxed after the jungle chip.


I checked around the board for any missing components related to the OSD and found that C17 wasn't there. Should I put one there? Should it be the same value as C14, C15, and C16?

[MarkOZLAD]

The jungle chip in this set requires 1-3V for RGB blanking but also has a mode when the blanking goes over 4V where the jungle RGB out is muted for osd overlay. (Due to the post mixed OSD)

Seems likely that you’ve somehow mucked up the blanking circuit such that the OSD blanking is no longer able to go above the 4V, though I cannot be sure.

These are generally about the easiest mod you can ever do so hard to pick what you’ve done wrong. The first thing I can think to do is to check the resistance between pin 16 of scart and ground. Should be 75 ohm.

[Trick-E]

So I'm in the middle of an RGB mod on a JVC C-1327 with the Toshiba TA8601AN Jungle IC, but have yet to see good results.
Has anyone successfully completed a working RGB mod on one of the JVC C series?

I have the chassis schematics, but only the datasheet for the TA8601BN, which is likely similar but not identical.

I've tapped into the RGB output of the Jungle chip (at the resistors just afterwards), and grabbed the Sync and Blanking directly from the chip pins, but don't have a clear signal.

Looks like sync isn't working, and while the screen goes black once I input an RGB signal, this happens whether or not the voltage goes to the blanking, and my input signal is barely visible.

Any help would be appreciated. I can add any necessary pics to clarify this post.

Trick