International Standards for Vertical Interval Test Signals

In the interests of facilitating the international exchange of television programs, the International Radio Consultative Committee (CCIR) at its XII Plenary Assembly in New Delhi in January-February of 1970 approved a new recommendation unendation for international vertical interval test signals. The recommendation covers both major television systems, the 625-line/50-field and 525-line/60-field systems, and specifies the lines in the vertical blanking interval that are to be reserved for this purpose. Additionally the recommendation details the specific waveforms, or test signal elements, for the 625-line/50-field systems. These waveforms represent the results of years of technical discussions among transmission experts of the countries involved. They are described in some detail for the information of U.S. broadcasters as well as broadcasters in other countries using the 52-line/ 60-field systems, since many of these same deliberations have also taken place and will continue to take place in the development of the international vertical interval test signal for 525-line/60-field transmissions.