Sega Master System 2 RGB mod not working

Hi,
I have followed this guide:
http://kaikoshumi.webs.com/mastersystemiimod.htm

But all I see is:


I have double checked everything and I can not see what is wrong. I can hear the sounds from the game but it is not very loud (dont know if that is normal)

Please help me

 

Hi
total newb myself, but done a bit of googleing, since i want do the same mod soon.

from http://www.smspower.org/Development/VideoOutput

Your horizontal sync seems to be off by just a tiny margin.

The guide in your link uses pin20.
(scart allows for some wierd hacks where the sender is free to put the whole composite signal on the sync line and the receiver deceides to either use that and ignore the rest - or - extract only the sync info from the composite signal and use rgb from the distinct lines)

Maybe also an adjustable capacitator and some wiggling on the sync line is enough.

Again - only posting in case no one else answers you, as i hardly have a clue myself.

 

Could you be more specific? What country are you in? Is that a CRT TV? Are you using SCART? Did you wire a SCART socket as per the guide and use a standard SCART cable? Which version motherboard do you have - is the chip a Sony?

It's either a sync issue or a switching issue, I'd imagine. Check that your switching voltage is correct first. Some TVs use pin 8 for RGB switching, which is why it's usually wired to pin 16, via a resistor - pin 16 only needs 1-3V for RGB switching.

If you're in America and/or using a monitor such as a PVM, you might need a sync stripper.

Why is there a resistor and capacitor on the composite line? That seems crazy. I'd try without them.

 

I think the composite video has the resistor and cap on the board usually. If you are soldering directly do the chip, you are bypassing the on board resistor and cap.

 

It's like a synch problem. Sometime when the TV doesn't autoswitch properly to the right AV channel, it does that.
I don't like autoswitch via pin 8 of the SCART/Péritel, so I never wire it (and it's not wired in kaikoshumi's guide). But you have to wire pin 16, it's for RGB activation.
First, try to manually switch to the right AV channel and see if you still get the same.