attempting SNES Component mod

[Niku-Sama]

ok I am trying this one out but I am having a bit of an issue with it.
it started out that it worked but everything was washed out, tried 75 ohm resistors on all 3 lines, still the same problem.
took the 75 ohm resistor off of Pr and Pb and it got a little better, changed the 75 ohm to 100 ohm on Y and again colors got a little better

recently changed 100 ohm to 120 ohm on Y and colors are almost there, I think 150 ohm will do it, but each step up the image gets darker. at 150 ohm it'll probably be too dark to compensate with the settings on the tv.

I'm at a loss here

if Y was washing out the colors of Pr and Pb and adding resistance to bring the colors out works but at the same time makes the screen darker do I need to amp Pr and Pb?
I read something about 1k pull down resistors between signal and ground on the lines but I think at this point that wont be any help.....

I donno!

[APE992]

Have you tried another TV?

The application circuit in the BA6592F datasheet shows a 1kohm pull down resistor for Pr and Pb but I don't think that is your issue (they're probably on the board anyway but you should check the traces to verify. I can't imagine they left the outputs connected to nothing). I'm also seeing some posts about putting 220uF capacitors on the Pr and Pb lines and 75ohm resistors. The capacitors I believe are there to block DC current while passing along video.

[Niku-Sama]

I have the same result with other TVs.
I forgot to say it's a sns-gpm-02 with an s-enc chip.

There was something else i was going to say and now i forgot

edit:

I remember now.
as far as the caps go I was getting 1.5 volts on Pr and Pb straight off the chip, which is normal forward voltage on an av line like that. the Y line was 1.7 volts so maybe I am going about this wrong, maybe I need to do the cap and bring that voltage down and use a lesser resistor and probably be ok then.

[Niku-Sama]

ok an update on this.
I had a hard time getting Y to jive with Pr and Pb so I wired up a variable resistor and adjusted it so it looked good in a few games (megaman x, Zelda, Mario world, Mario 2 on all stars) and it came out to be about 180 ohms on resistance.

no matter what Y always seemed to be about 0.2-0.6 volts higher than Pr and Pb sothis fixed that, fixed the washed out. It wasn't perfect but I got to thinking that most of my component stuff doesn't seem to pop as much as straight RGB and so I tested a PS2 on both a LCD and my PVM and it too seemed washed out on both but when I swapped it to analog RGB it was better so maybe its just me noticing the difference between RGB and Component, either way a minor brightness and chroma tweak on the PVM and it looks damn schecksy.

the levels being that far off on the system (see voltage difference) makes me think I may have been tapping into a different spot on the Y line than I was on the Pr and Pb. I was using the vias because I didn't want to solder directly to the chip wile I was testing and the vias had a better hold so I might have come into Y as it was being pumped or maybe I was getting Pr and Pb after going through resistors to bring them in spec and Y before resistors to being it in spec.

oh well. i'll be soldering directly to the chip before putting it all back together and I'll give it one last shot before wrapping it up with out a resistor on Y and see if its any different.

the resistance to normalize it was about 175 Ohms, closest I had was a 180 Ohm resistor so pretty darn close.

any other tips on potentially improving video quality on this one?

[Pikkon]

I have done a good number of component mods to the snes and yours is a sns-gpm-02,this is how I do it.

On the e-snec chip,pin 1 solder a cap,100 or 220uf,positive going to the leg,negative going to said jack,same with pin 24.

For green,grab it from the multiout and use a 75 to 100 resister.