Sec.  90.209   Bandwidth limitations.

   (a) Each authorization issued to a station licensed under this part will
   show an emission designator representing the class of emission authorized.
   The designator will be prefixed by a specified necessary bandwidth. This
   number does not necessarily indicate the bandwidth occupied by the emission
   at any instant. In those cases where  Sec. 2.202 of this chapter does not provide
   a  formula  for  the  computation of necessary bandwidth, the occupied
   bandwidth, as defined in part 2 of this chapter, may be used in lieu of the
   necessary bandwidth.

   (b)  The  maximum  authorized  single  channel  bandwidth  of emission
   corresponding to the type of emission specified in  Sec. 90.207 is as follows:

   (1) For A1A or A1B emissions, the maximum authorized bandwidth is 0.25 kHz.
   The maximum authorized bandwidth for type A3E emission is 8 kHz.

   (2)  For operations below 25 MHz utilizing J3E emission, the bandwidth
   occupied by the emission shall not exceed 3000 Hz. The assigned frequency
   will be specified in the authorization. The authorized carrier frequency
   will be 1400 Hz lower in frequency than the assigned frequency. Only upper
   sideband emission may be used. In the case of regularly available double
   sideband radiotelephone channels, an assigned frequency for J3E emissions is
   available  either  1600  Hz below or 1400 Hz above the double sideband
   radiotelephone assigned frequency.

   (3) For all other types of emissions, the maximum authorized bandwidth shall
   not be more than that normally authorized for voice operations.

   (4) Where a frequency is assigned exclusively to a single licensee, more
   than a single emission may be used within the authorized bandwidth. In such
   cases, the frequency stability requirements of  Sec. 90.213 must be met for each
   emission.

   (5) Unless specified elsewhere, channel spacings and bandwidths that will be
   authorized in the following frequency bands are given in the following
   table.

   Standard Channel Spacing/Bandwidth
   Frequency band (MHz) Channel spacing (kHz) Authorized bandwidth (kHz)
   Below 25^2                                
   25–50                                   20                         20
   72–76                                   20                         20
   150–174                              ^17.5             ^1,320/11.25/6
   216–220^5                             6.25                 20/11.25/6
   220–222                                  5                          4
   406–512^2                           ^16.25              ^1320/11.25/6
   806–809/851–854                       12.5                         20
   809–824/854–869                         25                         20
   896–901/935–940                       12.5                       13.6
   902–928^4                                 
   929–930                                 25                         20
   1427–1432^5                           12.5                       12.5
   ^32450–2483.5^2                           
   Above 2500^2                              

   ^1For stations authorized on or after August 18, 1995.

   ^2Bandwidths for radiolocation stations in the 420–450 MHz band and for
   stations operating in bands subject to this footnote will be reviewed and
   authorized on a case-by-case basis.

   ^3Operations using equipment designed to operate with a 25 kHz channel
   bandwidth will be authorized a 20 kHz bandwidth. Operations using equipment
   designed to operate with a 12.5 kHz channel bandwidth will be authorized a
   11.25 kHz bandwidth. Operations using equipment designed to operate with a
   6.25  kHz  channel bandwidth will be authorized a 6 kHz bandwidth. All
   stations must operate on channels with a bandwidth of 12.5 kHz or less
   beginning  January  1, 2013, unless the operations meet the efficiency
   standard of  Sec. 90.203(j)(3).

   ^4The maximum authorized bandwidth shall be 12 MHz for non-multilateration
   LMS  operations  in  the  band 909.75–921.75 MHz and 2 MHz in the band
   902.00–904.00 MHz. The maximum authorized bandwidth for multilateration LMS
   operations shall be 5.75 MHz in the 904.00–909.75 MHz band; 2 MHz in the
   919.75–921.75 MHz band; 5.75 MHz in the 921.75–927.25 MHz band and its
   associated 927.25–927.50 MHz narrowband forward link; and 8.00 MHz if the
   919.75–921.75  MHz  and  921.75–927.25  MHz bands and their associated
   927.25–927.50  MHz  and 927.50–927.75 MHz narrowband forward links are
   aggregated.

   ^5See  Sec. 90.259.

   (6)(i) Beginning January 1, 2011, no new applications for the 150–174 MHz
   and/or 421–512 MHz bands will be acceptable for filing if the applicant
   utilizes channels with an authorized bandwidth exceeding 11.25 kHz, unless
   specified elsewhere or the operations meet the efficiency standards of
    Sec. 90.203(j)(3).

   (ii) Beginning January 1, 2011, no modification applications for stations in
   the  150–174  MHz and/or 421–512 MHz bands that increase the station's
   authorized  interference contour, will be acceptable for filing if the
   applicant utilizes channels with an authorized bandwidth exceeding 11.25
   kHz,  unless specified elsewhere or the operations meet the efficiency
   standards of  Sec. 90.203(j)(3). See  Sec. 90.187(b)(2)(iii) and (iv) for interference
   contour designations and calculations. Applications submitted pursuant to
   this paragraph must comply with frequency coordination requirements of
    Sec. 90.175.

   [ 60 FR 37263 , July 19, 1995, as amended at  67 FR 41860 , June 20, 2002;  68 FR 42314 , July 17, 2003;  68 FR 54769 , Sept. 18, 2003;  69 FR 39867 , July 1,
   2004;  69 FR 67837 , Nov. 22, 2004;  70 FR 21661 , Apr. 27, 2005;  70 FR 34693 ,
   June 15, 2005;  72 FR 35194 , June 27, 2007;  73 FR 34201 , June 17, 2008]