§ 95.2779   MURS unwanted emissions limits.

   The requirements in this section apply to each MURS transmitter type
   both with and without the connection of attachments, such as an
   external microphone, power cord and/or antenna.

   (a) Emission masks. Emission masks applicable to transmitting equipment
   in the MURS are defined by the requirements in the following table. The
   numbers in the paragraphs column refer to attenuation requirement rule
   paragraph numbers under paragraph (b) of this section. The words “audio
   filter” refer to the audio filter described in § 95.2775.
   Channel center frequencies
   (MHz)                Paragraphs
         151.820, 151.880 and 151.940            (1), (2).
         154.570 & 154.600, with audio filter    (3), (4), (7).
         154.570 & 154.600, without audio filter (5), (6), (7).

   (1) Each MURS transmitter type that transmits F3E or G3E emissions on
   154.570 MHz or 154.600 MHz and incorporates an audio filter satisfying
   the requirements of § 95.2775 in its design may comply with the less
   stringent unwanted emissions attenuation requirements set forth in
   paragraphs (b)(3), (4), and (7) of this section.

   (2) Each MURS transmitter type that transmits on 154.570 MHz or 154.600
   MHz, but does not incorporate an audio filter satisfying the
   requirements of § 95.2775 in its design, must comply with the unwanted
   emissions attenuation requirements set forth in paragraphs (b)(5)
   through (7) of this section.

   (b) Attenuation requirements. The power of unwanted emissions must be
   attenuated below the transmitter output power in Watts (P) by at least:

   (1) 7.27(fd−2.88 kHz) dB on any frequency removed from the channel
   center frequency by a displacement frequency (fd in kHz) that is more
   than 5.625 kHz, but not more than 12.5 kHz.

   (2) 50 + 10 log (P) dB or 70 dB, whichever is the lesser attenuation,
   on any frequency removed from the channel center frequency by more than
   12.5 kHz.

   (3) 25 dB on any frequency removed from the channel center frequency by
   more than 10 kHz, but not more than 20 kHz.

   (4) 35 dB on any frequency removed from the channel center frequency by
   more than 20 kHz, but not more than 50 kHz.

   (5) 83 log (fd ÷ 5) dB on any frequency removed from the center of the
   authorized bandwidth by a displacement frequency (fd in kHz) that is
   more than 5 kHz, but not more than 10 kHz.

   (6) 29 log (fd2 ÷ 11) dB or 50 dB, whichever is the lesser attenuation
   on any frequency removed from the channel center frequency by a
   displacement frequency (fd in kHz) that is more than 10 kHz, but not
   more than 50 kHz.

   (7) 43 + 10 log(P) dB on any frequency removed from the channel center
   frequency by more than 50 kHz.

   (c) Measurement bandwidths. The power of unwanted emissions in the
   frequency bands specified in paragraphs (b)(1) and (3) through (6) of
   this section is measured with a reference bandwidth of 300 Hz. The
   power of unwanted emissions in the frequency ranges specified in
   paragraphs (b)(2) and (7) of this section is measured with a reference
   bandwidth of at least 30 kHz.

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