lidnariq wrote:Right, that's the big problem.
The jailbars that you showed are because it is the PPU itself that simultaneously drives both PPU A13 and the analog video output. (Probably. I think we've eliminated the capacitive coupling option?)
The power supply needs to be a lot firmer (more capacitors, with less ESR, a mix of both ceramic and electrolytic, shorter wires) to reduce the amount of visible jailbars.
Perhaps try moving the place where you supply the extra bonus 5V supply across the PPU's power and ground pins (if it's further away)
The jailbars that you showed are because it is the PPU itself that
simultaneously drives both PPU A13 and the analog video output. (Probably. I think we've eliminated the capacitive coupling option?)
The power supply needs to be a lot firmer (more capacitors, with less ESR, a mix of both ceramic and electrolytic, shorter wires) to reduce the amount of visible jailbars.
Perhaps try moving the place where you supply the extra bonus 5V supply across the PPU's power and ground pins (if it's further away)[/quote]
Ok I’ll have fun with capacitors
What do you recommend for capacitors values ?
All of them between the external 5v lines and the common ground ?
Thanks again man, you’ve really been a great help.