§  23.15   Emission limitations.

   (a) For all transmitters placed into operation after September 19,
   1973, and for all transmitters after September 19, 1975, which operate
   on frequencies below 30 MHz:

   (1) The occupied bandwidth of emission shall be confined within the
   least possible spectrum space consistent with the state of the art and
   the required quality of transmission, and in no event shall be more
   than the authorized bandwidth.

   (2) Spurious emissions of transmitters of mean power of 50 kilowatts or
   less shall be attenuated at least 40 decibels below the mean power of
   the fundamental without exceeding the power of 50 milliwatts.

   (3) Spurious emissions of transmitters of mean power exceeding 50
   kilowatts shall be attenuated at least 60 decibels below the mean power
   of the fundamental and every effort should be made to keep the level of
   spurious emissions below the power of 50 milliwatts.

   (b) For all transmitters placed into operation after September 19,
   1973, and for all transmitters after September 19, 1975, which operate
   on frequencies above 30 MHz, the mean powers of emissions shall be
   attenuated below the mean output power of the transmitter in accordance
   with the following schedule:

   (1) On any frequency removed from the assigned frequency by more than
   50 percent up to and including 100 percent of the authorized bandwidth:
   At least 25 decibels;

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

   (3) On any frequency removed from the assigned frequency by more than
   250 percent of the authorized bandwidth: at least 43 plus 10 log (mean
   output power in watts) decibels, or 80 decibels, whichever is the
   lesser attenuation.

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

   [ 38 FR 22479 , Aug. 21, 1973;  38 FR 24901 , Sept. 11, 1973]