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Discussion Starter #1 (Edited)
I decided to mod my Samsung 20" TV to take RGB using a SCART socket. This seems to be a more and more common thing to do if you don't want to spend $300 on a PVM but still want RGB. I had previously done an s-video mod which worked, but I had to adjust the picture settings between sources (probably because I didn't bother to do any impedance matching on the IC) and the sound amp died so I had to mess around with RCA breakout cables, stuff was coming unplugged, etc. Here is the stock composite/mono audio block. The previous owner busted his video cable and got the center pin stuck in the socket which was also giving me issues. Yeah... screw this. Let's rip that mess out.



I began by tying the OSD blanking input to the jungle IC's VCC using an unstuffed capacitor trace on the bottom of the board. This worked a treat and blocked the existing video inputs from displaying, only the OSD. Put down some quick dry glue for strain relief and to prevent shorts.



Removed 3 120Ω resistors for the RGB lines and tied in my signals here.



Next is the SCART socket. I wired RGB and composite sync grounds to the chassis ground followed by the signal wires. I removed any pins I didn't use to make the work easier and prevent shorts. I routed the composite sync and ground wires to their original pads on the PCB using the composite video pad to deliver sync. The board engineers placed the factory RCA plugs near the corresponding pins on the SCART block.





This worked great. A clean factory looking install that fits almost perfectly into the rear cover of the TV. I didn't realize I installed the port upside down (whoops!) and had to widen the hole slightly to get it to fit. Drilled two holes and threaded the socket for extra support screws. That hole was for my previous s-video socket.



I hooked up my PSX and PS2 (after switching to RGB mode to fix the green screen) and the results are pretty good! I will add some external pots for fine tuned impedance matching later. Right now the picture is a bit too bright as expected but it's definitely not bad. I'm not seeing any artifacts so a good clean RGB signal is reaching the electron guns. However, I did notice the OSD is still functional but you can barely see it. These signals, unlike in most cases, must be generated internally to the jungle IC (even though the schematics label these inputs as OSD signals).

So now essentially I have finally converted this TV into a proper RGB monitor with a standard SCART socket. I'll use an audio breakout adapter for sound. Very happy, colors are bright, blacks are deep, a success!











In this case I decided to make this change permanent, meaning I didn't install a switch so I could continue using NTSC inputs. This greatly simplified the process and I'm glad I didn't waste my time with it. I won't be missing NTSC.
 

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Very neat, nice work! What are the limitations in terms of resolution, etc.? I assume that it's still limited to 480i, correct? Did you do a lot of research on different TVs or was this the only model capable of it?
 

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Discussion Starter #3
Resolution and sync limitations of the chassis are the same, I am just delivering the signal in an unencoded form. Tested 240p and 480i without issues. There are dozens of models that are compatible with this mod, especially cheap ones like this that use a generic chassis. If you open up a TV and see a lot of unstuffed components of the chassis board it's a good indication of being a generic board. I have utilized/recycled some pads on the board, others completely restuff circuits that have been removed from US TVs to make their mods most authentic. It's largely a niche group of people that knows how to do this or even cares.
 

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Discussion Starter #5 (Edited)
I finally did my terminations am I really am blown away by the difference this makes. The whites are brighter! The colors are incredible! The blacks are excellent! And best of all, no color bleeding, dot crawl, or softening of the image! You really have to see it to believe it. I increased the saturation in these photos to best represent what you actually see. Pictures don't do it justice. There is very minor ringing/ghosting on the right edge of some images, this may be due to this TV having a monitored RGB input. I would say Rayman is the best demonstration of sheer color and artistry. I am EXTREMELY pleased with the results and can't believe what I have been missing out on for the last 20 years as an American gamer. We REALLY got shafted with NTSC.

The green in this volume meter is almost overpowering. Crazy color!


Rayman's overworld screen is brilliant with hues, and the scanlines are clean and sharp.


Pay particularly close attention to the red eraser and Eat at Joe's sign. Absolutely no color bleeding as commonly found in NTSC.


A good demonstration of contrast. Again, no smearing of the reds.


You can make out the individual pixels of the memory card icons!


Text is 100% readable without NTSC's dot crawl.


Even Rayman 2, a much darker tone, is easy on the eyes.


More super clean text. This would otherwise be very difficult or impossible to read.


The skate shop in Tony Hawk's Proskater 4 is oozing with detail.


I can make out several logos in RGB.


I can now see little nuances in the graphics, such as banding in some texture gradients.
 
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