Sec.  74.551   Equipment changes.

   (a) Modifications may be made to an existing authorization in accordance
   with  Sec.  Sec. 1.929 and 1.947 of this chapter.

   (b) Permissible changes in equipment operating in the bands 18.3–18.58,
   18.76–18.82 GHz and 19.1–19.16 GHz. Notwithstanding other provisions of this
   section, licensees of stations that remain co-primary under the provisions
   of  Sec. 74.502(c) may not make modifications to their systems that increase
   interference to satellite earth stations, or result in a facility that would
   be more costly to relocate.

   [ 28 FR 13716 , Dec. 14, 1963, as amended at  38 FR 6827 , Mar. 13, 1973;  47 FR 54448 , Dec. 3, 1982;  49 FR 7130 , Feb. 27, 1984;  50 FR 48599 , Nov. 26, 1985;
    58 FR 19775 , Apr. 16, 1993;  61 FR 4368 , Feb. 6, 1996;  65 FR 54172 , Sept. 7,
   2000;  68 FR 12768 , Mar. 17, 2003;  68 FR 16967 , Apr. 8, 2003;  68 FR 20225 ,
   Apr. 24, 2003;  69 FR 43772 , July 22, 2004]