Section 73.618 - Antenna location and principal community coverage(a) The TV antenna location shall be chosen so that, on the basis of the effective radiated power (ERP) and antenna height above average terrain (HAAT) employed, the following minimum F(50,90) field strength in dB above one uV/m will be provided over the entire principal community to be served: Table 1 to Paragraph (a)-Minimum Field Strength Required Over Principal Community
| dBu |
| Channels 2-6 | 35 |
| Channels 7-13 | 43 |
| Channels 14-36 | 48 |
(b) The location of the antenna must be so chosen that there is not a major obstruction in the path over the principal community to be served.(c) For the purposes of this section, coverage is to be determined in accordance with § 73.619(b) . Under actual conditions, the true coverage may vary from these estimates because the terrain over any specific path is expected to be different from the average terrain on which the field strength charts were based. Further, the actual extent of service will usually be less than indicated by these estimates due to interference from other stations. Because of these factors, the predicted field strength contours give no assurance of service to any specific percentage of receiver locations within the distances indicated.