§ 74.1236   Emission and bandwidth.

   (a)  The license of a station authorized under this subpart allows the
   transmission of either F3 or other types of frequency modulation (see § 2.201
   of this chapter) upon a showing of need, as long as the emission complies
   with the following:

   (1) For transmitter output powers no greater than 10 watts, paragraphs (b),
   (c), and (d) of this section apply.

   (2) For transmitter output powers greater than 10 watts, § 73.317 (a), (b),
   (c), and (d) apply.

   (b)  Standard  width FM channels will be assigned and the transmitting
   apparatus shall be operated so as to limit spurious emissions to the lowest
   practicable value. Any emissions including intermodulation products and
   radiofrequency harmonics which are not essential for the transmission of the
   desired aural information shall be considered to be spurious emissions.

   (c) The power of emissions appearing outside the assigned channel shall be
   attenuated below the total power of the emission as follows:
   Distance of emission from center frequency Minimum attenuation below
   unmodulated carrier
   120 to 240 kHz 25 dB
   Over 240 and up to 600 kHz 35 dB
   Over 600 kHz 60 dB

   (d) Greater attenuation than that specified in paragraph (c) of this section
   may be required if interference results outside the assigned channel.

   [ 35 FR 15388 , Oct. 2, 1970, as amended at  52 FR 31406 , Aug. 20, 1987;  55 FR 50698 , Dec. 10, 1990]

   return arrow Back to Top