Wavy Interference Fix for Xbox RGB

[RARusk]

In my "Wavy Interference in Xbox RGB" topic thread, I discussed how I traced the problem to the +5VDC line on the Xbox A/V port. This interference affected me because I used the +5VDC line from the Xbox to power my RGB box which contains a amplifier and a sync chip. This problem also affects those who purchased a X2VGA device from Neoya or those who use RF modulators. This interference happens only on newer Xbox motherboard revisions. Older machines are not affected.

I solved my problem by hooking up my RGB box to a switching power supply and using the +5VDCsb line from it. But I still wanted to solve the interference problem so I could go back to using power from my consoles. Neoya managed to solve the problem in it's new X2VGA+ and I was intrigued by how they solved it. Had to be small and simple so it could fit inside the case.

So I went and played around with some capacitors and had no success. Today, I went to Atex Electronics (here in San Antonio) and got some inductors and ferrite cores. I hooked up the RGB board back up to the Xbox power line and hooked up the board to a breadboard and started experimenting.

Lo and behold, success!  :lol:

The solution is to run the +5VDC line through either an inductor or ferrite core. In the picture below, at the bottom is a 3.9uh inductor, above that is a 2.7uh coil, and on the breadboard is a ferrite core (which I later installed in the RGB board). All the parts pictured work in removing the interference. Worked great with my PlayStation2 also.

Unless there is very little room within the X2VGA device it should not be too hard to hack an inductor or ferrite core to clean up the power line within the box.

[RARusk]

By the way, this is my RGB board......

To the left is the plug that I use my custom cables to hook up the box to the console. The monitor and audio plugs are to the right. The square blob on the bottom is the EL1883 chip. Near the top, under the electrical tape (to hold it down) is the motherboard cutout (from a Genesis 1) that contains the CXA-1145 RGB chip that is wired as an amplifier. You can also see the three 220uf caps in the middle. The gray wire is the +5VDC line that was soldered to another wire so it could be hooked up to the breadboard (the soldered connection is under the electrical tape near the caps).