Germany's second television network, ZDF, began offering stereo programs in 1984. For analog TV (PAL and NTSC), various modulation schemes are used in different parts of the world to broadcast more than one sound channel. These are sometimes used to provide two mono sound channels that are in different languages, rather than stereo. Multichannel television sound is used mainly in the Americas. NICAM is widely used in Europe, except in Germany, where Zweikanalton is used. The EIAJ FM/FM subcarrier system is used in Japan. For Digital TV, MP2 audio streams are widely used within MPEG-2 program streams. Dolby Digital is the audio standard used for Digital TV in North America, with the capability for anywhere between 1 and 6 discrete channels. MTS: Stereo for television In 1979, The New York Times reported, "What has prompted the [television] industry to embark on establishing high-fidelity [sound] standards now, according to engineering executives involved in the project, is chiefly the rapid march of the new television technologies, especially those that are challenging broadcast television, such as the video disk." Multichannel television sound, better known as MTS (often still as BTSC, for the Broadcast Television Systems Committee that created it), is the method of encoding three additional audio channels into an NTSC-format audio carrier. It was adopted by the FCC as the United States standard for stereo television transmission in 1984. Sporadic network transmission of stereo audio began on NBC on July 26, 1984, with The Tonight Show Starring Johnny Carson although at the time, only the network's New York City flagship station, WNBC-TV, had stereo broadcast capability. Regular stereo transmission of programs began in 1985. Recording methods A-B technique: time-of-arrival stereophony This uses two parallel omnidirectional microphones some distance apart, capturing time-of-arrival stereo information as well as some level (amplitude) difference information especially if employed in close proximity to the sound source(s). At a distance of about , the time delay (time-of-arrival difference) for a signal reaching the first microphone and then the other one from the side is approximately 1.5 ms (1 to 2 ms). If you increase the distance between the microphones, you effectively decrease the pickup angle. At a distance, it is approximately equivalent to the pickup angle of the near-coincident ORTF setup. This technique can produce phase issues when the stereo signal is mixed to mono. X-Y technique: intensity stereophony Here, two directional microphones are at the same place,