Page:United States Statutes at Large Volume 49 Part 2.djvu/573

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TELECOMMUNICATION CONVENTION. DECEMBER 9, 1932. 2589 APPENDIX 2 Appendix 2. Table of Frequency-band Widths Occupied by the Emissions (Sel' article 6) Generally, the frequency bands actually used by the different types of transmission at the present state of the art are indicated below: Type ot transmission Telegraphy, speed of 100 words per minute, Morse code (40 dots per second) on unmodulated continuous Width ot the band in cycles per second (Including both sidebands) waves.................... From80to240(correspondingtothe fundamental keying frequency and to its third harmonic). on modulated continuous waves. Same figure as above, plus twice the modulation frequency. Transmission of still pictures .. .. Approximately the ratio between the number of picture elements 1 to be transmitted and the number of sec· onds necessary for the transmission. Example: 100,000: 100= 1,000. Television ....•. .. .. .. .. .. ... . I Approximately the product of the number of picture elements 1 in a single picture multiplied by the number of pictures transmitted per second. Example: 10,000X20= 200,000. Commercial radiotelephony..... About 6,000. High-quality radiotelephony, as, for instance, in broadcasting. About 10,000 to 20,000. 1 A cycle Is composed of two elements. one black and one white; the modulation freqneDCY Ulerefore .. one balf ot the Dumber of elements transmitted per lIICOucl. Anu, p. 2453. Table.