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.
I'd imagine it's too bright as you don't have the 75ohm resistors to ground on the TV side. These in combination with the 75ohm series resistors on the rgb output form a voltage divider to half the voltage.