§ 74.861   Technical requirements.

   (a) Except as specified in paragraph (e) of this section, transmitter
   power is the power at the transmitter output terminals and delivered to
   the antenna, antenna transmission line, or any other impedance-matched,
   radio frequency load. For the purpose of this subpart, the transmitter
   power is the carrier power.

   (b) Each authorization for a new low power auxiliary station shall
   require the use of certificated equipment. Such equipment shall be
   operated in accordance with the emission specifications included in the
   certification grant and as prescribed in paragraphs (c) through (e) of
   this section.

   (c) Low power auxiliary transmitters not required to operate on
   specific carrier frequencies shall operate sufficiently within the
   authorized frequency band edges to insure the emission bandwidth falls
   entirely within the authorized band.

   (d) For low power auxiliary stations operating in the bands other than
   those allocated for TV broadcasting, the following technical
   requirements are imposed.

   (1) For all bands except the 1435-1525 MHz band, the maximum
   transmitter power which will be authorized is 1 watt. In the 1435-1525
   MHz band, the maximum transmitter power which will be authorized is 250
   milliwatts. Licensees may accept the manufacturer's power rating;
   however, it is the licensee's responsibility to observe specified power
   limits.

   (2) If a low power auxiliary station employs amplitude modulation,
   modulation shall not exceed 100 percent on positive or negative peaks.

   (3) For the 26.1-26.480 MHz, 161.625-161.775 MHz, 450-451 MHz, and
   455-456 MHz bands, the occupied bandwidth shall not be greater than
   that necessary for satisfactory transmission and, in any event, an
   emission appearing on any discrete frequency outside the authorized
   band shall be attenuated, at least, 43+10 log10 (mean output power, in
   watts) dB below the mean output power of the transmitting unit. The
   requirements of this paragraph shall also apply to the applications for
   certification of equipment for the 944-952 MHz band until January 13,
   2018.

   (4)(i) For the 653-657 MHz, 941.5-944 MHz, 944-952 MHz, 952.850-956.250
   MHz, 956.45-959.85 MHz, 1435-1525 MHz, 6875-6900 MHz and 7100-7125 MHz
   bands, analog emissions within the band from one megahertz below to one
   megahertz above the carrier frequency shall comply with the emission
   mask in section 8.3.1.2 of the European Telecommunications Institute
   Standard ETSI EN 300 422-1 v1.4.2 (2011-08), Electromagnetic
   compatibility and Radio spectrum Matters (ERM); Wireless microphones in
   the 25 MHz to 3 GHz frequency range; Part 1: Technical characteristics
   and methods of measurement. Beyond one megahertz below and above the
   carrier frequency, emissions shall comply with the limits specified in
   section 8.4 of ETSI EN 300 422-1 v1.4.2 (2011-08).

   (ii) For the 653-657 MHz, 941.5-944 MHz, 944-952 MHz, 952.850-956.250
   MHz, 956.45-959.85 MHz, and 1435-1525 MHz bands, digital emissions
   within the band from one megahertz below to one megahertz above the
   carrier frequency shall comply with the emission mask in section
   8.3.2.2 (Figure 4) of the European Telecommunications Institute
   Standard ETSI EN 300 422-1 v1.4.2 (2011-08), Electromagnetic
   compatibility and Radio spectrum Matters (ERM); Wireless microphones in
   the 25 MHz to 3 GHz frequency range; part 1: Technical characteristics
   and methods of measurement. Beyond one megahertz below and above the
   carrier frequency, emissions shall comply with the limits specified in
   section 8.4 of ETSI EN 300 422-1 v1.4.2 (2011-08).

   (iii) In the 6875-6900 MHz and 7100-7125 MHz bands, digital emissions
   within the band from one megahertz below to one megahertz above the
   carrier frequency shall comply with the emission mask in section
   8.3.2.2 (Figure 5) of the European Telecommunications Institute
   Standard ETSI EN 300 422-1 v1.4.2 (2011-08), Electromagnetic
   compatibility and Radio spectrum Matters (ERM); Wireless microphones in
   the 25 MHz to 3 GHz frequency range; part 1: Technical characteristics
   and methods of measurement. Beyond one megahertz below and above the
   carrier frequency, emissions shall comply with the limits specified in
   section 8.4 of ETSI EN 300 422-1 v1.4.2 (2011-08).

   (iv) For the 944-952 MHz band, the requirements of this paragraph
   (d)(4) shall not apply to the applications for certification of
   equipment for that band until nine months after release of the
   Commission's Channel Reassignment Public Notice, as defined in section
   73.3700(a)(2) of this chapter.

   (e) For low power auxiliary stations operating in the 600 MHz duplex
   gap and the bands allocated for TV broadcasting, the following
   technical requirements apply:

   (1) The power may not exceed the following values.

   (i) 54-72, 76-88, and 174-216 MHz bands: 50 mW EIRP

   (ii) 470-608 and 614-698: 250 mW conducted power

   (iii) 600 MHz duplex gap: 20 mW EIRP

   (2) Transmitters may be either crystal controlled or frequency
   synthesized.

   (3) Any form of modulation may be used. A maximum deviation of ±75 kHz
   is permitted when frequency modulation is employed.

   (4) The frequency tolerance of the transmitter shall be 0.005 percent.

   (5) The operating bandwidth shall not exceed 200 kHz.

   (6) The mean power of emissions shall be attenuated below the mean
   output power of the transmitter in accordance with the following
   schedule:

   (i) On any frequency removed from the operating frequency by more than
   50 percent up to and including 100 percent of the authorized bandwidth:
   at least 25 dB;

   (ii) On any frequency removed from the operating frequency by more than
   100 percent up to and including 250 percent of the authorized
   bandwidth: at least 35 dB;

   (iii) On any frequency removed from the operating frequency by more
   than 250 percent of the authorized bandwidth: at least 43 + 10log10
   (mean output power in watts) dB.

   (7) Analog emissions within the band from one megahertz below to one
   megahertz above the carrier frequency shall comply with the emission
   mask in section 8.3.1.2 of the European Telecommunications Institute
   Standard ETSI EN 300 422-1 v1.4.2 (2011-08), Electromagnetic
   compatibility and Radio spectrum Matters (ERM); Wireless microphones in
   the 25 MHz to 3 GHz frequency range; part 1: Technical characteristics
   and methods of measurement. Digital emissions within the band from one
   megahertz below to one megahertz above the carrier frequency shall
   comply with the emission mask in section 8.3.2.2 (Figure 4) of the
   European Telecommunications Institute Standard ETSI EN 300 422-1 v1.4.2
   (2011-08), Electromagnetic compatibility and Radio spectrum Matters
   (ERM); Wireless microphones in the 25 MHz to 3 GHz frequency range;
   part 1: Technical characteristics and methods of measurement. Beyond
   one megahertz below and above the carrier frequency, emissions shall
   comply with the limits specified in section 8.4 of ETSI EN 300 422-1
   v1.4.2 (2011-08). The requirements of this paragraph (e)(7) shall not
   apply to applications for certification of equipment in these bands
   until nine months after release of the Commission's Channel
   Reassignment Public Notice, as defined in § 73.3700(a)(2) of this
   chapter.

   (f) Unusual transmitting antennas or antenna elevations shall not be
   used to deliberately extend the range of low power auxiliary stations
   beyond the limited areas defined in § 74.831.

   (g) Low power auxiliary stations shall be operated so that no harmful
   interference is caused to any other class of station operating in
   accordance with Commission's rules and regulations and with the Table
   of Frequency Allocations in part 2 thereof.

   (h) In the event a station's emissions outside its authorized frequency
   band causes harmful interference, the Commission may, at its
   discretion, require the licensee to take such further steps as may be
   necessary to eliminate the interference.

   (i) The materials listed in this section are incorporated by reference
   in this part. These incorporations by reference were approved by the
   Director of the Federal Register in accordance with 5 U.S.C. 552(a) and
   1 CFR part 51. These materials are incorporated as they exist on the
   date of the approval, and notice of any change in these materials will
   be published in the Federal Register. All approved material is
   available for inspection at the Federal Communications Commission, 445
   12th St. SW., Reference Information Center, Room CY-A257, Washington,
   DC 20554, (202) 418-0270 and is available from the sources below. It is
   also available for inspection at the National Archives and Records
   Administration (NARA). For information on the availability of this
   material at NARA, call (202) 741-6030, or go to:
   http://www.archives.gov/federal__register/code__of__federal__regulation
   s/ibr__locations.html.

   (1) European Telecommunications Standards Institute, 650 Route des
   Lucioles, 06921 Sophia Antipolis Cedex, France. A copy of the standard
   is also available at
   http://www.etsi.org/deliver/etsi__en/300400__300499/30042201/01.03.02__
   60/en__30042201v010302p.pdf.

   (i) ETSI EN 300 422-1 V1.4.2 (2011-08): “Electromagnetic compatibility
   and Radio spectrum Matters (ERM); Wireless microphones in the 25 MHz to
   3 GHz frequency range; Part 1: Technical characteristics and methods of
   measurement,” Copyright 2011, IBR approved for section 15.236(g).

   (ii) [Reserved]

   (2) [Reserved].

   (Sec. 5, 48 Stat. 1068; 47 U.S.C. 155)

   [ 43 FR 13576 , Mar. 31, 1978, as amended at  52 FR 2535 , Jan. 23, 1987;
    63 FR 36605 , July 7, 1998;  75 FR 3639 , Jan. 22, 2010;  80 FR 71730 , Nov.
   17, 2015;  80 FR 73085 , Nov. 23, 2015;  82 FR 41561 , Sept. 1, 2017]

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