Sec. 90.317  Fixed ancillary signaling and data transmissions.

    (a) Licensees of systems that have exclusive-use status in their 
respective geographic areas may engage in fixed ancillary signaling and 
data transmissions, subject to the following requirements:
    (1) All such ancillary operations must be on a secondary, non-
interference basis to the primary mobile operation of any other 
licensee.
    (2) The output power at the remote site shall not exceed 30 watts.
    (3) Any fixed transmitters will not count toward meeting the mobile 
loading requirements nor be considered in whole or in part as a 
justification for authorizing additional frequencies in the licensee's 
mobile system.
    (4) Automatic means must be provided to deactivate the remote 
transmitter in the event the carrier remains on for a period in excess 
of three minutes.
    (5) Operational fixed stations authorized pursuant to the provisions 
of this paragraph are exempt from the requirements of Secs. 90.425 and 
90.429.
    (6) If the system is licensed on 470-512 MHz conventional 
frequencies, and exclusivity has been achieved through

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the aggregate loading of more than a single co-channel licensee, then a 
licensee must obtain the concurrence of other co-channel licensees prior 
to commencing such ancillary operations.
    (b) Licensees of systems that do not have exclusive-use status in 
their respective geographic areas may conduct fixed ancillary signaling 
and data transmissions only in accordance with the provisions of 
Sec. 90.235 of this part.
[ 57 FR 34693 , Aug. 6, 1992]

         Subpart M--Transportation Infrastructure Radio Service

    Source:   60 FR 15253 , Mar. 23, 1995, unless otherwise noted.