Page:United States Statutes at Large Volume 55 Part 2.djvu/136

This page needs to be proofread.

55 STAT.] NORTHfAMERICAN-REGIONAL BROADCASTING-DEC. 13, 1937 6. Objectionable interference. Objectionable interference is the degree of interference produced when, at a specified boundary or field intensity contour with respect to the desired station, the field intensity of an undesired station (or the root-mean -square value of field inten- sities of two or more stations on the same frequency) exceeds for ten (10) percent or more of the time the values hereinafter set forth in this Agreement. 7. Power. The power of a radio transmitter is the power supplied to the antenna. The power in the antenna of a modulated-wave transmitter shall be expressed in two numbers, one indicating the power of the carrier frequency supplied to the antenna, and the other the actual maximum percentage of modulation. 8. Spurious radiation. A spurious radiation from a transmitter is any radiation outside the frequency band of emission normal for the type of transmission employed, including any harmonic modulation products, key clicks, parasitic oscillations and other transient effects. 9. English, French and Spanish equivalents. It is agreed that, as used in this Agreement, the French and Spanish words below set forth are respectively the equivalent of, and mean the same as, the English terms opposite which they appear: English French Spanish Clear channel Frequence libre Canal despejado Objectionable interference Brouillage nuisible Interferencia objetable B. CLASSES OF CHANNELS AND ALLOCATION THEREOF 1. Three classes: The 106 channels in the standard broadcast band are divided into three principal classes: clear, regional and local. 2. Clear channel: A clear channel is one on which the dominant station or stations render service over wide areas and which are cleared of objectionable interference, within their primary service areas and over all or a substantial portion of their secondary service areas. 3. Regional channel: A regional chalnnel is one on which several stations may operate with powers not in excess of 5 kw. The primary service area of a station operating on any such channel may be limited, as a consequence of interference, to a given field intensity contour. 4. Local channel: A local channel is one on which several stations may operate with powers not in excess of 250 watts. The primary service area of a station operating on any such channel may be limited, as a consequence of interference, to a given field intensity contour. 5. Number of channels of each class: The number of channels of each class shall be as follows: Clear channels 59 Regional channels 41 Local channels 6 106 1007