§ 74.707   Low power TV and TV translator station protection.

   (a)(1) A low power TV or TV translator will be protected from interference
   from other low power TV or TV translator stations, or TV booster stations
   within the following predicted contours:

   (i) 62 dBu for stations on Channels 2 through 6;

   (ii) 68 dBu for stations on Channels 7 through 13; and

   (iii) 74 dBu for stations on Channels 14 through 69.

   Existing licensees and permittees that did not furnish sufficient data
   required to calculate the above contours by April 15, 1983 are assigned
   protected contours having the following radii:

   Up to 0.001 kW VHF/UHF—1 mile (1.6 km) from transmitter site

   Up to 0.01 kW VHF; up to 0.1 k/W UHF—2 miles (3.2 km) from transmitter site

   Up to 0.1 kW VHF; up to 1 kW UHF—4 miles (6.4 km) from transmitter site

   New applicants must submit the required information; they cannot rely on
   this table.

   (2)  The  low  power  TV or TV translator station protected contour is
   calculated from the authorized effective radiated power and antenna height
   above average terrain, using Figure 9, 10, or 10b of § 73.699 (F(50,50)
   charts) of Part 73 of this chapter.

   (b)(1) An application to construct a new low power TV, TV translator, or TV
   booster station or change the facilities of an existing station will not be
   accepted if it specifies a site which is within the protected contour of a
   co-channel or first adjacent channel low power TV, TV translator, or TV
   booster station, except that a TV booster station may be located within the
   protected contour of its co-channel primary station.

   (2) Due to the frequency spacing which exists between TV Channels 4 and 5,
   between Channels 6 and 7, and between Channels 13 and 14, adjacent channel
   protection standards shall not be applicable to these pairs of channels.
   (See § 73.603(a) of Part 73 of this chapter.)

   (3) A UHF low power TV, TV translator, or TV booster construction permit
   application will not be accepted if it specifies a site within the UHF low
   power TV, TV translator, or TV booster station's protected contour and
   proposes operation on a channel that is 15 channels above the channel in use
   by the low power TV, TV translator, or TV booster station.

   (c) The low power TV, TV translator, or TV booster construction permit
   application  field  strength is calculated from the proposed effective
   radiated  power  (ERP) and the antenna above average terrain (HAAT) in
   pertinent directions.

   (1) For co-channel protection, the field strength is calculated using Figure
   9a, 10a, or 10c of § 73.699 (F(50,10) charts) of Part 73 of this chapter.

   (2) For low power TV, TV translator, or TV booster applications that do not
   specify the same channel as the low power TV, TV translator, or TV booster
   station to be protected, the field strength is calculated using Figure 9,
   10, or 10b of § 73.699 (F(50,50) charts) of Part 73 of this chapter.

   (d) A low power TV, TV translator, or TV booster station application will
   not be accepted if the ratio in dB of its field strength to that of the
   authorized  low  power TV, TV translator, or TV booster station at its
   protected contour fails to meet the following:

   (1)  −45 dB for co-channel operations without offset carrier frequency
   operation or −28 dB for offset carrier frequency operation. An application
   requesting offset carrier frequency operation must include the following:

   (i) A requested offset designation (zero, plus, or minus) identifying the
   proposed  direction  of  the  10  kHz offset from the standard carrier
   frequencies of the requested channel. If the offset designation is not
   different from that of the station being protected, or if the station being
   protected is not maintaining its frequencies within the tolerance specified
   in § 74.761 for offset operation, the −45 dB ratio must be used.

   (ii) A description of the means by which the low power TV, TV translator, or
   TV booster station's frequencies will be maintained within the tolerances
   specified in § 74.761 for offset operation.

   (2) 6 dB when the protected low power TV or TV translator station operates
   on a VHF channel that is one channel above the requested channel.

   (3) 12 dB when the protected low power TV or TV translator station operates
   on a VHF channel that is one channel below the requested channel.

   (4) 15 dB when the protected low power TV or TV translator station operates
   on a UHF channel that is one channel above or below the requested channel.

   (5) 6 dB when the protected low power TV or TV translator station operates
   on a UHF channel that is fifteen channels below the requested channel.

   (e) As an alternative to the preceding paragraphs of § 74.707, an applicant
   for a low power TV or TV translator station may make full use of terrain
   shielding and Longley-Rice terrain dependent propagation prediction methods
   to demonstrate that the proposed facility would not be likely to cause
   interference  to  low power TV, TV translator and TV booster stations.
   Guidance on using the Longley-Rice methodology is provided in OET Bulletin
   No. 69 (but also see § 74.793(d)). Copies of OET Bulletin No. 69 may be
   inspected  during normal business hours at the: Federal Communications
   Commission,  Room CY-C203, 445 12th Street, SW., Reference Information
   Center, Washington, DC 20554. This document is also available through the
   Internet on the FCC Home Page at http://www.fcc.gov.

   [ 47 FR 21498 , May 18, 1982, as amended at  47 FR 35990 , Aug. 18, 1982;  48 FR 21487 , May 12, 1983;  52 FR 31403 , Aug. 20, 1987;  62 FR 26722 , May 14, 1997;
    65 FR 58467 , Sept. 29, 2000;  69 FR 69332 , Nov. 29, 2004]

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