Sec. 90.691  Emission mask requirements for EA-based systems.

    (a) Out-of-band emission requirement shall apply only to the 
``outer'' channels included in an EA license and to spectrum adjacent to 
interior channels used by incumbent licensees. The emission limits are 
as follows:
    (1) For any frequency removed from the EA licensee's frequency block 
by up to and including 37.5 kHz, the power of any emission shall be 
attenuated below the transmitter power (P) in watts by at least 116 
Log10(f/6.1) decibels or 50 + 10 Log10(P) decibels 
or 80 decibels, whichever is the lesser attenuation, where f is the 
frequency removed from the center of the outer channel in the block in 
kilohertz and where f is greater than 12.5 kHz.
    (2) For any frequency removed from the EA licensee's frequency block 
greater than 37.5 kHz, the power of any emission shall be attenuated 
below the

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transmitter power (P) in watts by at least 43 + 10Log10(P) 
decibels or 80 decibels, whichever is the lesser attenuation, where f is 
the frequency removed from the center of the outer channel in the block 
in kilohertz and where f is greater than 37.5 kHz.
    (b) When an emission outside of the authorized bandwidth causes 
harmful interference, the Commission may, at its discretion, require 
greater attenuation than specified in this section.