Sec.  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]