In simple terms, a modification performed on a games console
player?) that gives a video
output in RGB
It is generally agreed that RGB is the best way to connect a console to a telly or monitor, giving richer cleaner colours, and a far sharper image; but for some strange reason, not all consoles provide an RGB output. However, by examining the traces at various points on the circuit boards of these consoles, some friendly blokes located points on the board where RGB signals are available. Most RGB mods take the form of a SCART cable, hardwired to the consoles circuit board. This is pretty unsafe however, as the wires can easily come loose if propper stress relief jackets are not used. Some people perform RGB mods by adding an extra socket at an empty space on the consoles casing. A custom SCART lead can then be connected to this socket. Another type of RGB mod is where the connector is already in place on the console, but the requisite pins have not been wired to the board to save money, such as on the Nintendo 64, and redesigned SNES. In this case, all that must be done is that the pins be correctly wired up.
RGB mods are most common in Europe, where the majority of televisions have RGB SCART inputs. In fact, until NTSC compatibility became common-place, they were a requirement for most imported consoles. PAL TVs could usually, or with slight adjustments to the vertical hold, display a 60Hz signal, but unless the PAL colour system is used it would be in black and white. To correct this, an RGB signal from the console was required to bypass the video decoding circuit. This was how gamers in Europe got to experience the PC Engine, and other consoles of the early nineties. The SNES and Mega Drive both featured RGB output, so all that had to be done was purchase a SCART lead (although US and Japanese/PAL SNESs cannot use the same type of SCART lead). The 3DO presented a particular problem for importers, because RGB traces were nowhere to be seen on the board. Eventually, the problem was solved using an S-Video to RGB convertor box. When the PlayStation and Saturn arrived, many gamers performed RGB mods on their hot off the shelf consoles rather than waiting for official SCART leads to appear.
In america, RGB inputs on televisions are not so common. Most people who desire RGB quality resort to using an RGB monitor such as the Commodore 1084.
The act of performing an RGB mod is often called "SCARTing", and RGB modded consoles are sometimes referd to as "SCART consoles."
See also: lockout bypass, 50/60 switch, mod chip.