PALplus

PALplus (or PAL+) is an analogue television broadcasting system aimed to improve and enhance the PAL format while remaining compatible with existing television receivers. It followed experiences with the HD-MAC and D2-MAC, hybrid analogue-digital formats that were incompatible with PAL receivers. It was developed in Germany University of Dortmund in cooperation with German terrestrial broadcasters and European and Japanese manufacturers.

In the 1980s a new high definition broadcasting standard, HD-MAC, was created, offering twice the number of available scanning lines compared to PAL. As a transitional standard, D2-MAC was established. It had same number of lines as PAL, but like HD-MAC it was designed for widescreen content. The MAC family of standards was adopted in Europe in 1983 primarily for Direct Broadcasting by Satellite (DBS) services.

European terrestrial broadcasters felt the need to better position themselves in order to compete with satellite and cable operators. PALplus was the name of a strategy group founded in 1989 to develop an enhanced system for terrestrial transmission compatible with PAL. While not attempting to produce HDTV standards of quality, the new format was meant to improve PAL in the following areas:

In the beginning, the task group consisted of the public broadcasting corporations of Germany (ARD and ZDF), Austria (ORF), Switzerland (SRG) and the United Kingdom (BBC and UKIB, United Kingdom Independent Broadcasters) together with the consumer electronics manufacturers Grundig, Nokia, Philips and Thomson. Sony as well as the Spanish and Portuguese broadcasters joined the group later on.

At the 1993 International Consumer Electronics Exhibition in Berlin, the first experimental PALplus broadcasts began. At the same year, the European Union approved a plan to support the production and broadcast of 16:9 programs.

In 1994 broadcasts began adopting the format and Nokia launched the first PALplus TV set in Germany.

Evaluations, performed by ITU and EBU engineers in 1995-1998 concluded that the use of down-converted HDTV source material, as well as high-quality widescreen standard definition content, could be a significant benefit to the PALplus picture quality. Moreover, the experts felt that PALplus would not be out of place in an HDTV environment at viewing distances equal or farther to four heights of a television set.

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