WHAT IS PAL

Short for “Phase Alternating Line”, is a colour encoding system used in broadcast television systems in large parts of the world. The PAL TV standard was introduced in the early 1960's in Europe. The term PAL may also be used to describe any video, including digital video, formatted for playback on a PAL TV.

This generally includes any Standard Definition (SD) video with a vertical Resolution of up to 576 Pixels and a horizontal resolution no greater than 720, which also has a Framerate of 25fps. PAL may also be called 625/50, in reference to the total number of lines (including lines not in the Active Area) and fieldrate.

PAL is the predominant video system or standard mostly used overseas. In PAL, 25 frames are transmitted each second. Each frame is made up of 625 individual scan lines and a refresh rate of 50 interlaced fields per second (i.e. 25 full frames per second), such as systems B, G, H, I, and N.

Although the PAL frame contains 625 lines, only 576 are used for display; the others are reserved for Teletext (data and captioning). Teletext is only visible with a special decoder, and does not interfere with regular image transmission.

P A L Phase Alternating Line
SYSTEM	PAL	PAL N	PAL M
Line/Field	625/50	625/50	525/60
Horizontal Freq.	15.625 kHz	15.625 kHz	15.750 kHz
Vertical Freq.	50 Hz	50 Hz	60 Hz
Color Sub Carrier	4.433618 MHz	3.582056 MHz	3.575611 MHz
Video Bandwidth	5.0 MHz	4.2 MHz	4.2 MHz
Sound Carrier	5.5 MHz	4.5 MHz	4.5 MHz

Due to the way in which PAL signal conversions occur, it generally has better color quality and consistency than NTSC, although the actual color range is slightly less.

PAL generally has a better depth of field and contrast ratio than NTSC. There may be a slightly yellowish tint to the picture due to a slower scan rate.

Many video adapters that enable computer monitors to be used as television screens support both NTSC and PAL signals. PAL broadcasting for television is being replaced by digital DVB-T.