47 CFR 74.703 - Interference.
(a) An application for a new low power TV, TV translator, or TV booster station or for a change in the facilities of such an authorized station will not be granted when it is apparent that interference will be caused. Except where there is a written agreement between the affected parties to accept interference, or where it can be shown that interference will not occur due to terrain shielding and/or Longley-Rice terrain dependent propagation methods, the licensee of a new low power TV, TV translator, or TV booster shall protect existing low power TV and TV translator stations from interference within the protected contour defined in § 74.707 and shall protect existing Class A TV and digital Class A TV stations within the protected contours defined in § 73.6010 of this chapter. Such written agreement shall accompany the application. Guidance on using the Longley-Rice methodology is provided in OET Bulletin No. 69. Copies of OET Bulletin No. 69 may be inspected during normal business hours at the: Federal Communications Commission, 445 12th Street, S.W., Reference Information Center (Room CY-A257), Washington, DC 20554. This document is also available through the Internet on the FCC Home Page at http://www.fcc.gov/oet/info/documents/bulletins/#69.
(b) It shall be the responsibility of the licensee of a low power TV, TV translator, or TV booster station to correct at its expense any condition of interference to the direct reception of the signal of any other TV broadcast analog station and DTV station operating on the same channel as that used by the low power TV, TV translator, or TV booster station or an adjacent channel which occurs as a result of the operation of the low power TV, TV translator, or TV booster station. Interference will be considered to occur whenever reception of a regularly used signal is impaired by the signals radiated by the low power TV, TV translator, or TV booster station, regardless of the quality of the reception or the strength of the signal so used. If the interference cannot be promptly eliminated by the application of suitable techniques, operation of the offending low power TV, TV translator, or TV booster station shall be suspended and shall not be resumed until the interference has been eliminated. If the complainant refuses to permit the low Power TV, TV translator, or TV booster station to apply remedial techniques that demonstrably will eliminate the interference without impairment of the original reception, the licensee of the low power TV, TV translator, or TV booster station is absolved of further responsibility. TV booster stations will be exempt from the provisions of this paragraph to the extent that they may cause limited interference to their primary stations' signal subject to the conditions of paragraph (g) of this section.
(c) It shall be the responsibility of the licensee of a low power TV, TV translator, or TV booster station to correct any condition of interference which results from the radiation of radio frequency energy outside its assigned channel. Upon notice by the FCC to the station licensee or operator that such interference is caused by spurious emissions of the station, operation of the station shall be immediately suspended and not resumed until the interference has been eliminated. However, short test transmissions may be made during the period of suspended operation to check the efficacy of remedial measures.
(d) When a low-power TV or TV translator station causes interference to a CATV system by radiations within its assigned channel at the cable headend or on the output channel of any system converter located at a receiver, the earlier user, whether cable system or low-power TV or TV translator station, will be given priority on the channel, and the later user will be responsible for correction of the interference. When a low-power TV or TV translator station causes interference to a BRS or EBS system by radiations within its assigned channel on the output channel of any system converter located at a receiver, the earlier user, whether BRS system or low-power TV or TV translator station, will be given priority on the channel, and the later user will be responsible for correction of the interference.
(e) Low power TV and TV translator stations are being authorized on a secondary basis to existing land mobile uses and must correct whatever interference they cause to land mobile stations or cease operation.
(f) It shall be the responsibility of a digital low power TV or TV translator station operating on a channel from channel 52-69 to eliminate at its expense any condition of interference caused to the operation of or services provided by existing and future commercial or public safety wireless licensees in the 700 MHz bands. The offending digital LPTV or translator station must cease operations immediately upon notification by any primary wireless licensee, once it has been established that the digital low power TV or translator station is causing the interference.
(g) An existing or future wireless licensee in the 700 MHz bands may notify (certified mail, return receipt requested), a digital low power TV or TV translator operating on the same channel or first adjacent channel of its intention to initiate or change wireless operations and the likelihood of interference from the low power TV or translator station within its licensed geographic service area. The notice should describe the facilities, associated service area and operations of the wireless licensee with sufficient detail to permit an evaluation of the likelihood of interference. Upon receipt of such notice, the digital LPTV or TV translator licensee must cease operation within 120 days unless:
(1) It obtains the agreement of the wireless licensee to continue operations;
(2) The commencement or modification of wireless service is delayed beyond that period (in which case the period will be extended); or
(3) The Commission stays the effect of the interference notification, upon request.
(h) In each instance where suspension of operation is required, the licensee shall submit a full report to the FCC in Washington, DC, after operation is resumed, containing details of the nature of the interference, the source of the interfering signals, and the remedial steps taken to eliminate the interference.
(i) A TV booster station may not disrupt the existing service of its primary station nor may it cause interference to the signal provided by the primary station within the principal community to be served.