Statistics of Full Power and Class a Television Stations in the United States As of February 22, 2012
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Full Power and Class A Television Stations Statistics of Full Power and Class A Television Stations in the United States as of February 22, 2012 Report No. TAB 2013-01 by Robert Weller Mark Colombo Chris Gao Washington, DC 20554 July 16, 2013 1 Full Power and Class A Television Stations (Intentionally left blank) 2 Full Power and Class A Television Stations Introduction This report presents the underlying data and results of a statistical study of authorized effective radiated power (ERP), channel use and other engineering parameters for full-power digital television (DTV) and Class A television stations in the United States, including Alaska, the District of Columbia, Guam, Hawaii, Puerto Rico, and the U.S. Virgin Islands. This study is similar in scope and content to one published in 1974,1 but also includes data on Class A television stations, a service which did not exist at that time. The study covers the following major areas: 1. Listing of full-power and Class A television stations operating as of February 22, 20122 2. Channel use of stations 3. Antenna height (HAAT) of full-power VHF and UHF stations 4. Power (ERP) of full-power and Class A VHF and UHF stations 5. Maps showing distribution of stations by channel 6. Electrical beam tilt of full-power VHF and UHF stations 7. CDBS extract (a complete CDBS file is available as a separate download from http://data.fcc.gov/download/incentive-auctions/OET-69/ Background HAAT. In the study of the distribution of antenna heights of full-power stations, average terrain is used as a reference. Average terrain for television stations is defined in Section 73.684(d) of FCC rules, and is generally the average of the terrain elevations along the eight cardinal radials from the transmit antenna site, between 3.2 and 16.1 kilometers from the site. The antenna height above average terrain (HAAT) is the difference between the height of the antenna radiation center above mean sea level and the average calculated value of the eight, radial average terrains surrounding the antenna site. Figure 1 illustrates the HAAT determination for one radial direction. HAAT is not reported for Class A stations. 1 Wang, John C.H., “A Report on Antenna and Power Statistics of Television Stations in the United States,” FCC/OCE Report RS74-04, December 1974. 2 Also included are the facilities specified in certain construction permits granted before February 22, 2012, for stations licensed after that date, certain channel substitutions, certain digital conversion facilities of Class A stations, and two construction permits that were granted pursuant to court order. See the accompanying Public Notice for details. 3 Full Power and Class A Television Stations Figure 1. Relationship of height above average terrain (HAAT) to antenna height and surrounding terrain. TV Zones. Television broadcast zones in the U.S.A. are defined in Section 73.609 of FCC rules. A map showing the approximate boundaries of those zones is presented as Figure 2. Under the allotment rules for DTV, Zones 2 and 3 are treated as one zone; that is, the facility limitations and definitions are identical for both zones. Class A stations are generally not assigned to a broadcast zone and the Class A facility limitations do not vary by location. Figure 2. Map showing approximate boundaries of television broadcast zones in the U.S. 4 Full Power and Class A Television Stations ERP. The authorized effective radiated power is the maximum value in any direction or angle. Polarization. FCC rules require that television stations transmit a horizontally-polarized wave, but stations may add a vertically-polarized component in phase quadrature at a power level up to that of the horizontal polarization to achieve elliptical or circular polarization of the transmitted wave. Since the total radiated power is increased by up to a factor of two by this method, improved coverage may result. Information about transmitted signal polarization is generally not reported for Class A stations. Data Source. The television station technical data used in the preparation of this report were generally taken from the FCC’s Consolidated Database for the Broadcast Services (CDBS) dated February 22, 2012.2 The technical facilities used are intended to represent a snapshot of actual station operations on that date. Often, stations are authorized to construct or operate more than one facility; in those cases, only the data associated with the facility actually operating are used. The data were generally taken from the relevant sections of applications for construction permit or applications for license as contained in CDBS. Since the individual stations were not contacted to verify operational status and the engineering parameters were not independently verified, there is some uncertainty about the accuracy of the underlying data, but we believe these data to accurately reflect station operation in almost all cases. There are procedures to allow licensees to correct data that they believe to be incorrect. A total of 2,224 stations were considered in this analysis, including 1,774 full-power conventional DTV stations, 12 full-power DTS stations,3 and 438 Class A stations. A listing of the some of the salient engineering specifications for the facilities considered is contained in Appendix B. Summary There were 1,786 full-power stations operating in the 50 states, the District of Columbia, Guam, Puerto Rico, and the U.S. Virgin Islands as of February 22, 2012.2 The typical full-power DTV station transmits with horizontal polarization only from a directional antenna having 0.75 electrical beam tilt at a height of about 365 meters above average terrain on a UHF channel (14–51) at a maximum radiated power of about 500 kilowatts. Channel utilization is shown in Figure A. Antenna heights above average terrain are distributed about a mean of 408 meters (median of 365 meters). There are allotment power level breakpoints in the FCC’s rules at 305 meters. (See Section 73.622(f) of FCC rules). Distributions of antenna HAAT are shown in Figures B1–B2. Median values can be read directly from the graphs of cumulative distribution. ERP values for VHF operations, both low- and high-band, are distributed about a mean that is well below the maximum power levels permitted in the rules. ERP values for VHF channel assignments are generally more restrictive in Zone 1. (See Section 73.622(f) of FCC rules). Distributions by ERP (and by zone for VHF stations) for each television broadcast band are given in Figures C1–C6. There were 438 Class A stations operating in the 50 states, DC, Guam, Puerto Rico, and the U.S. Virgin Islands as of February 22, 2012.4 Slightly more than half (226 stations) of all Class A stations operate using digital transmission facilities. All Class A stations are required to convert from analog to 3 DTS or Distributed Transmission System stations operate more than one transmission facility on a common channel. The engineering parameters of each transmission facility (apart from channel) are generally different so these stations are considered separately from conventional full-power DTV stations. 5 Full Power and Class A Television Stations digital operation by September 1, 2015.5 The typical Class A station operates on a UHF channel using a directional antenna. Channel utilization is shown in Figure A. Distributions of ERP for Class A VHF and UHF operation are provided separately for analog and digital operations in Figures D. About 14% of full-power stations operate using elliptical or circular polarization. Nearly all UHF stations (98%) and the majority of VHF stations (74%) utilize electrical beam tilt. Distributions of electrical beam tilt are provided in Figure E. Information concerning polarization is not included for Class A stations. 4 A number of stations that had Class A status on February 22, 2012 no longer have that status and are not included in this analysis. 5 See “Amendment of Parts 73 and 74 of the Commission’s Rules to Establish Rules for Digital Low Power Television, Television Translator, and Television Booster Stations and to Amend Rules for Digital Class A Television Stations,” Second Report and Order, MB-03-185, Released July 15, 2011. 6 Full Power and Class A Television Stations Summary Statistics Station Totals Total number of operating, full-service stations as of February 22, 2012: .............1,786 (incl. 12 DTS) Number of full-power stations in Zone 1: ................................................................445 (incl. 3 DTS) Number of full-power stations in Zones 2 and 3: .................................................1,341 (incl. 9 DTS) Total number of operating, Class A stations ............................................... 438 (226 digital, 212 analog) Channel Usage Number of full-power stations operating on Channels 2—6: ....................................40 Number of Class A stations operating on Channels 2—6: ............................16 Number of stations operating on Channels 7—13: ..................................................422 (incl. 1 DTS) Number of Class A stations operating on Channels 7—13: ..........................35 Number of stations operating on Channels 14—51: .............................................1,324 (incl. 11 DTS) Number of Class A stations operating on Channels 14—51: ......................387 Effective Radiated Power (ERP)6 Mean ERP of full-power stations (all zones) on Channels 2—6: ..............................15.0 kW Mean ERP of full-power stations (Zone 1) on Channels 2—6: .................................11.9