§ 90.221   Adjacent channel power limits.

   (a) For the frequency bands indicated below, operations using equipment
   designed to operate with a 25 kHz channel bandwidth may be authorized up to
   a 22 kHz bandwidth if the equipment meets the adjacent channel power (ACP)
   limits below. The table specifies a value for the ACP as a function of the
   displacement from the channel center frequency and a measurement bandwidth
   of 18 kHz.

   (b)(1) Maximum adjacent power levels for frequencies in the 450-470 MHz
   band:
   Frequency offset Maximum ACP (dBc) for devices 1 watt and less Maximum ACP
   (dBc) for devices above 1 watt
   25 kHz −55 dBc −60 dBc
   50 kHz −70 dBc −70 dBc
   75 kHz −70 dBc −70 dBc

   (2) In any case, no requirement in excess of −36 dBm shall apply.

   (c)(1) Maximum adjacent power levels for frequencies in the 809-824/854-869
   MHz band:
   Frequency offset Maximum ACP (dBc) for devices less than 15 watts Maximum
   ACP (dBc) for devices 15 watts and above
   25 kHz −55 dBc −55 dBc
   50 kHz −65 dBc −65 dBc
   75 kHz −65 dBc −70 dBc

   (2) In any case, no requirement in excess of −36 dBm shall apply.

   (d) On any frequency removed from the assigned frequency by more than 75
   kHz, the attenuation of any emission must be at least 43 + 10 log (Pwatts)
   dB.

   [ 77 FR 61538 , Oct. 10, 2012]

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Subpart J—Non-Voice and Other Specialized Operations

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