RF
In the beginning, all signals went through the RF (radio-frequency, or antenna) input. An RF TV signal contains luminance (black and white), color, and audio signals all mashed together in a complex way that the TV set has to sort out before delivering picture and sound. It’s not a pretty process–something is always lost in the translation–but there is no avoiding it with broadcast TV.
Scart
Widely used in Europe the 21-pin SCART connector has been around since the late 80’s It can carry Composite, S-Video or RGB video signals as well as stereo audio. It also has pins reserved for data switching which are today used for such as auto 16:9 Widescreen switching and smart systems for control video recording devices.
Composite Video
Term used to describe systems that output all colour, sync and black levels down one cable. Avoid using this type of signal at all costs.
SVHS/S-Video (Y/C)
S-video simply means separated video.The brightness (Y) and color © signals carried by separate wires within the cable. (Hence, another name you may see for S-video is Y/C.) Since the signals are never combined, they don’t need to be separated. That’s a benefit because the process of combination and separation is never perfect, losing detail and creating subtly (or sometimes not so subtly) annoying errors, such as dots crawling along sharp edges or moiré effects on tightly patterned fabrics.
RGB Video
RGB stands for Red Green and Blue, these are the 3 colours used to display a TV picture. Using RGB the picture is sent as three separate colours corresponding to the three colours used in a TV to display the picture. A high resolution RGB picture can have a bandwidth of over 10MHz and this is without doubt the best way to send picture information to a TV or display. RGB requires a seperate timing signal. This can be sent seperately -RGB+s or more commonly down green RGsB. Green is used because our eyes are less sensitive to green and therfore less likely to perceive any degredation in the signal.
RGB+HV
This is basically the same as RGB above but the sync signals are seperated into their native horizontal and vertical components and are also slightly higher voltage, making them suitable for longer cable runs. This method of connection is used to connect pc’s to their monitors and plasma screens to video processors etc. RGB+HV requires no further processing by the tv to display the picture
Component Video (Y/U/V) (Y/Pr/Pb)
A high quality video connection found on video sources like DVD and of course on display devices like plasma, projection etc. Component Video can also be used for carrying the signal when DVD players have Progressive Scan output Labelled as “Y” “Pr” and “Pb”. “Y” is luminance, luma, or “Brightness” This describes the level of white (or black). “Pr” is the level of Red “Pb” is the Level of Blue The green section of the final colour output is derived from the levels of red, blue and white level, whatever the difference present in the the white level after subtracting blue and red must be green. This is the format used to store video information on DVD’s.