Mega Drive 2 dark RGB

Started by Darkman, October 24, 2005, 02:30:03 AM

Previous topic - Next topic

Darkman

After accidentaly finding MiniDIN9 plugs for sale, I quickly made an RGB cable for my PAL Mega Drive 2. The output is rather dark. Not unplayably dark, but much darker than it was with composite cable. I removed the 220uF caps and the visual became a bit lighter(still too dark), but now the screen brightnes is uneven - the upper left corner is brighter and fades to dark going to the lower right. It also seems to pulsate slowly. This Mega Drive 2 has a '93 motherboard with a Fujitsu video encoder chip. Do I need an RGB amp or is my wiring wrong?

Edit: turns out I needed a resistor of a few kOhms on the sync line. Everything's fine now.

Flash McCloud

OK, Dont start removing stuff just cause it aint working right.

you shoudl put the Caps back in to get an even brightness and go here MMMonkey RGB Booster Yes is if for the N64, but it is only because the N64 has this standard problem.  

MMMonkey says you need:
  • a RGB cable, which you have
  • Vero Board (4 tracks by 9 holes) [bout �2-3 for a 20-30 x 18-20 piece which can be trimmed]
  • 3 x 100uF 10v Capacitors (your Scart lead may already have these)
  • 3 x BF494 Si-N 260MHz Transistors
  • 3 x 1K5 ohm Resistors
  • 2 x 75 ohm Resistors
  • Selection of short wires

    You'll need to make a circuit like this:
    [img=http://img448.imageshack.us/img448/3230/n64boostdiagram9bx.gif]

    there is more info on the site.

Flash McCloud

OK, Dont start removing stuff just cause it aint working right.

you shoudl put the Caps back in to get an even brightness and go here MMMonkey RGB Booster Yes is if for the N64, but it is only because the N64 has this standard problem.  

MMMonkey says you need:
  • a RGB cable, which you have
  • Vero Board (4 tracks by 9 holes) [bout �2-3 for a 20-30 x 18-20 piece which can be trimmed]
  • 3 x 100uF 10v Capacitors (your Scart lead may already have these)
  • 3 x BF494 Si-N 260MHz Transistors
  • 3 x 1K5 ohm Resistors
  • 2 x 75 ohm Resistors
  • Selection of short wires
You'll need to make a circuit like this:


there is more info on the site.