47 C.F.R. § 73.62 Directional antenna system tolerances.
Title 47 - Telecommunication
(a) Each AM station operating a directional antenna must maintain the indicated relative amplitudes of the antenna monitor currents within 5% of the values specified therein. Directional antenna relative phase currents must be maintained to within ±3 deg. of the values specified on the instrument of authorization. (b) Whenever the operating parameters of a directional antenna cannot be maintained within the tolerances specified in paragraph (a) of this section, the following procedures will apply: (1) The licensee shall measure and log every monitoring point at least once for each mode of directional operation. Subsequent variations in operating parameters will require the remeasuring and logging of every monitoring point to assure that the authorized monitoring point limits are not being exceeded. (2) Provided each monitoring point is within its specified limit, operation may continue for a period up to 30 days before a request for Special Temporary Authority (STA) must be filed, pursuant to paragraph (b)(4) of this section, to operate with parameters at variance from the provisions of paragraph (a) of this section. (3) If any monitoring point exceeds its specified limit, the licensee must either terminate operation within 3 hours or reduce power in accordance with the applicable provisions of §73.1350(d), in order to eliminate any possibility of interference or excessive radiation in any direction. (4) If operation pursuant to paragraph (b)(3) of this section is necessary, or before the 30 day period specified in paragraph (b)(2) of this section expires, the licensee must request a Special Temporary Authority (STA) in accordance with §73.1635 to continue operation with parameters at variance and/or with reduced power along with a statement certifying that all monitoring points will be continuously maintained within their specified limits. (5) The licensee will be permitted 24 hours to accomplish the actions specified in paragraph (b)(1) of this section; provided that, the date and time of the failure to maintain proper operating parameters has been recorded in the station log. (c) In any other situation in which it might reasonably be anticipated that the operating parameters might vary out of tolerance (such as planned array repairs or adjustment and proofing procedures), the licensee shall, before such activity is undertaken, obtain an STA in accordance with §73.1635 in order to operate with parameters at variance and/or with reduced power as required to maintain all monitoring points within their specified limits. [50 FR 30946, July 31, 1985, as amended at 60 FR 55480, Nov. 1, 1995; 66 FR 20755, Apr. 25, 2001]
Title 47: Telecommunication
PART 73—RADIO BROADCAST SERVICES
Subpart A—AM Broadcast Stations
§ 73.62 Directional antenna system tolerances.
