§ 24.133   Emission limits.

   (a) The power of any emission shall be attenuated below the transmitter
   power (P), as measured in accordance with § 24.132(f), in accordance with the
   following schedule:

   (1) For transmitters authorized a bandwidth greater than 10 kHz:

   (i) On any frequency outside the authorized bandwidth and removed from the
   edge of the authorized bandwidth by a displacement frequency (fd in kHz) of
   up to and including 40 kHz: at least 116 Log10 ((fd + 10)/6.1) decibels or
   50  plus 10 Log10 (P) decibels or 70 decibels, whichever is the lesser
   attenuation;

   (ii) On any frequency outside the authorized bandwidth and removed from the
   edge of the authorized bandwidth by a displacement frequency (fd in kHz) of
   more  than 40 kHz: at least 43 + 10 Log10 (P) decibels or 80 decibels,
   whichever is the lesser attenuation.

   (2) For transmitters authorized a bandwidth of 10 kHz:

   (i) On any frequency outside the authorized bandwidth and removed from the
   edge of the authorized bandwidth by a displacement frequency (fd in kHz) of
   up to and including 20 kHz: at least 116 × Log10 ((fd + 5)/3.05) decibels or
   50  +  10 × Log10 (P) decibels or 70 decibels, whichever is the lesser
   attenuation;

   (ii) On any frequency outside the authorized bandwidth and removed from the
   edge of the authorized bandwidth by a displacement frequency (fd in kHz) of
   more than 20 kHz: at least 43 + 10 Log 10 (P) decibels or 80 decibels,
   whichever is the lesser attenuation.

   (b) The measurements of emission power can be expressed in peak or average
   values provided they are expressed in the same parameters as the transmitter
   power.

   (c) When an emission outside of the authorized bandwidth causes harmful
   interference,  the  Commission may, at its discretion, require greater
   attenuation than specified in this section.

   (d) The following minimum spectrum analyzer resolution bandwidth settings
   will be used: 300 Hz when showing compliance with paragraphs (a)(1)(i) and
   (a)(2)(i)  of  this  section;  and 30 kHz when showing compliance with
   paragraphs (a)(1)(ii) and (a)(2)(ii) of this section.

   [ 58 FR 59183 , Nov. 8, 1993. Redesignated at  59 FR 18499 , Apr. 19, 1994, as
   amended at  59 FR 14119 , Mar. 25, 1994;  66 FR 10968 , Feb. 21, 2001]

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