Sec. 78.103  Emissions and emission limitations.

    (a) A CARS station may be authorized to employ any type of emission, 
for which there are technical standards incorporated in Subpart D of 
this part, suitable for the simultaneous transmission of visual and 
aural television signals.
    (b) Any emission appearing on a frequency outside of the channel 
authorized for a transmitter shall be attenuated below the power of the 
emission in accordance with the following schedule:
    (1) For stations using FM or double sideband AM transmission:
    (i) On any frequency above the upper channel limit or below the 
lower channel limit by between zero and 50 percent of the authorized 
channel width: At least 25 decibels below the mean power of the 
emission;
    (ii) On any frequency above the upper channel limit or below the 
lower channel limit by more than 50 percent and up to 150 percent of the 
authorized channel width: At least 35 decibels below the mean power of 
the emission; and
    (iii) On any frequency above the upper channel limit or below the 
lower channel limit by more than 150 percent of the authorized channel 
width: At least 43+10 log10 (power in watts) decibels below 
the mean power of the emission.
    (2) For CARS stations using vestigial sideband AM transmission: At 
least 50 decibels below the peak power of the emission.
    (c) For operation in the 17.7.7-19.7 GHz band:
    The mean power of any emission shall be attenuated below the mean 
output power of the transmitter in accordance with the following 
schedule:
    (1) When using frequency modulation:
    (i) On any frequency removed from the assigned (center) frequency by 
more than 50% up to and including 100% of the authorized bandwidth: At 
least 25 dB;
    (ii) On any frequency removed from the assigned (center) frequency 
by more than 100% up to and including 250% of the authorized bandwidth: 
At least 35 dB;
    (iii) On any frequency removed from the assigned (center) frequency 
by more than 250% of the authorized bandwidth: At least 43+10 log 10 
(mean output power in watts) dB, or 80 dB, whichever is the lesser 
attenuation.
    (2) When using digital modulation:
    (i) In any 1 MHz band, the center frequency of which is removed from 
the assigned frequency by more than 50% up to and including 250% of the 
authorized bandwidth: As specified by the following equation but in no 
event less than 11 dB.

A=11+0.4 (P-50)+10 log10 B

where:
A=Attenuation (in dB) below the mean output power level.
P=Percent removed from the carrier frequency.
B=Authorized bandwidth in MHz.

    [Attenuation greater than 56 decibels is not required.]
    (ii) In any 4 kHz band, the center frequency of which is removed 
from the assigned frequency by more than 250% of the authorized 
bandwidth: At least 43=10 log10 (mean output power in watts) 
dB, or 80 dB, whichever is the lesser attenuation.
    (3) Amplitude Modulation:
    For vestigial sideband AM video: On any frequency removed from the 
center frequency of the authorized band by more than 50%: at least 50 dB 
below peak power of the emission.
    (d) In the event that interference to other stations is caused by 
emissions outside the authorized channel, the Commission may require 
greater attenuation than that specified in paragraph (b) of this 
section.
    (e) The maximum bandwidth that will be authorized per frequency 
assignment is set out in the table that follows. Regardless of the 
maximum

[[Page 684]]

authorized bandwidth specified for each frequency band, the Commission 
reserves the right to issue a license for less than the maximum 
bandwidth if it appears that a bandwidth less than the maximum would be 
sufficient to support an applicant's intended communications.

                                                                        
------------------------------------------------------------------------
                                            Maximum authorized bandwidth
           Frequency band (MHz)                         (MHz)           
------------------------------------------------------------------------
1,990 to 2,110............................  17 or 18.                   
6,425 to 6,525............................  8 or 25.                    
6,875 to 7,125............................  25.                         
12,700 to 13,250..........................  25.                         
17,700 to 19,700..........................  80.                         
31,000 to 31,300..........................  25 or 50.                   
------------------------------------------------------------------------


[ 37 FR 3292 , Feb. 12, 1972, as amended at  37 FR 15927 , Aug. 8, 1972;  38 FR 16648 , June 25, 1973;  39 FR 26025 , July 16, 1974;  48 FR 50736 , Nov. 
3, 1983;  49 FR 37779 , Sept. 26, 1984;  52 FR 7145 , Mar. 9, 1987]