§ 90.242   Travelers' information stations.

   (a) The frequencies 530 through 1700 kHz in 10 kHz increments may be
   assigned to the Public Safety Pool for the operation of Travelers'
   Information Stations subject to the following conditions and
   limitations.

   (1) [Reserved]

   (2) Each application for a station or system shall be accompanied by:

   (i) A statement certifying that the transmitting site of the Travelers'
   Information Station will be located at least 15 km (9.3 miles) measured
   orthogonally outside the measured 0.5 mV/m daytime contour (0.1 mV/m
   for Class A stations) of any AM broadcast station operating on a first
   adjacent channel or at least 130 km (80.6 miles) outside the measured
   0.5 mV/m daytime contour (0.1 mV/m for Class A stations) of any AM
   broadcast station operating on the same channel, or, if nighttime
   operation is proposed, outside the theoretical 0.5 mV/m-50% nighttime
   skywave contour of a U.S. Class A station. If the measured contour is
   not available, then the calculated 0.5 mV/m field strength contour
   shall be acceptable. These contours are available at the concerned AM
   broadcast station and FCC offices in Washington, DC.

   (ii) In consideration of possible cross-modulation and inter-modulation
   interference effects which may result from the operation of a
   Travelers' Information Station in the vicinity of an AM broadcast
   station on the second or third adjacent channel, the applicant shall
   certify that it has considered these possible effects and, to the best
   of its knowledge, does not foresee interference occurring to broadcast
   stations operating on second or third adjacent channels.

   (iii) A map showing the geographical location of each transmitter site
   and an estimate of the signal strength at the contour of the desired
   coverage area. For a cable system, the contour to be shown is the
   estimated field strength at 60 meters (197 feet) from any point on the
   cable. For a conventional radiating antenna, the estimated field
   strength contour at 1.5 km (0.93 mile) shall be shown. A contour map
   comprised of actual on-the-air measurements shall be submitted to the
   Commission within 60 days after station authorization or completion of
   station construction, whichever occurs later. A sufficient number of
   points shall be chosen at the specified distances (extrapolated
   measurements are acceptable) to adequately show compliance with the
   field strength limits.

   (iv) For each transmitter site, the transmitter's output power, the
   type of antenna utilized, its length (for a cable system), its height
   above ground, distance from transmitter to the antenna, and the
   elevation above sea level at the transmitting site.

   (3) Travelers' Information Stations will be authorized on a primary
   basis on 530 kHz and on a secondary basis to stations authorized on a
   primary basis in the band 535-1705 kHz.

   (4) A Travelers' Information Station authorization may be suspended,
   modified, or withdrawn by the Commission without prior notice or right
   to hearing if necessary to resolve interference conflicts, to implement
   agreements with foreign governments, or in other circumstances
   warranting such action.

   (5) The transmitting site of each Travelers' Information Station shall
   be restricted to the immediate vicinity of the following specified
   areas: Air, train, and bus transportation terminals, public parks and
   historical sites, bridges, tunnels, and any intersection of a Federal
   Interstate Highway with any other Interstate, Federal, State, or local
   highway.

   (6) A Travelers' Information Station shall normally be authorized to
   use a single transmitter. However, a system of stations, with each
   station in the system employing a separate transmitter, may be
   authorized for a specific area provided sufficient need is demonstrated
   by the applicant.

   (7) Travelers' Information Stations shall transmit only noncommercial
   voice information pertaining to traffic and road conditions, traffic
   hazard and travel advisories, directions, availability of lodging, rest
   stops and service stations, and descriptions of local points of
   interest. It is not permissible to identify the commercial name of any
   business establishment whose service may be available within or outside
   the coverage area of a Travelers' Information Station. However, to
   facilitate announcements concerning departures/arrivals and parking
   areas at air, train, and bus terminals, the trade name identification
   of carriers is permitted. Travelers' Information Stations may also
   transmit information in accordance with the provisions of § § 90.405 and
   90.407.

   (b) Technical standards. (1) The use of 6K00A3E emission will be
   authorized, however N0N emission may be used for purposes of receiver
   quieting, but only for a system of stations employing “leaky” cable
   antennas.

   (2) A frequency tolerance of 100 Hz shall be maintained.

   (3) For a station employing a cable antenna, the following restrictions
   apply:

   (i) The length of the cable antenna shall not exceed 3.0 km (1.9
   miles).

   (ii) Transmitter RF output power shall not exceed 50 watts and shall be
   adjustable downward to enable the user to comply with the specified
   field strength limit.

   (iii) The field strength of the emission on the operating frequency
   shall not exceed 2 mV/m when measured with a standard field strength
   meter at a distance of 60 meters (197 feet) from any part of the
   station.

   (4) For a station employing a conventional radiating antenna(s) (ex.
   vertical monopole, directional array) the following restrictions apply:

   (i) The antenna height above ground level shall not exceed 15.0 meters
   (49.2 feet).

   (ii) Only vertical polarization of antennas shall be permitted.

   (iii) Transmitter RF output power shall not exceed 10 watts to enable
   the user to comply with the specified field strength limit.

   (iv) The field strength of the emission on the operating frequency
   shall not exceed 2 mV/m when measured with a standard field strength
   meter at a distance of 1.50 km (0.93 miles) from the transmitting
   antenna system.

   (5) For co-channel stations operating under different licenses, the
   following minimum separation distances shall apply:

   (i) 0.50 km (0.31 miles) for the case when both stations are using
   cable antennas.

   (ii) 7.50 km (4.66 miles) for the case when one station is using a
   conventional antenna and the other is using a cable antenna.

   (iii) 15.0 km (9.3 miles) for the case when both stations are using
   conventional antennas.

   (6) For a system of co-channel transmitters operating under a single
   authorization utilizing either cable or conventional antennas, or both,
   no minimum separation distance is required.

   (7) An applicant desiring to locate a station that does not comply with
   the separation requirements of this section shall coordinate with the
   affected station.

   (8) Each transmitter in a Travelers' Information Station shall be
   equipped with an audio low-pass filter. Such filter shall be installed
   either at the transmitter's audio input or between the modulation
   limiter and the modulated stage. At audio frequencies between 5 kHz and
   20 kHz this filter shall have an attenuation greater than the
   attenuation at 1 kHz by at least:

   83 log10 (f/5) decibels.

   where “f” is the audio frequency in kHz. At audio frequencies above 20
   kHz, the attenuation shall be at least 50 decibels greater than the
   attenuation at 1 kHz.

   [ 43 FR 54791 , Nov. 22, 1978;  44 FR 67118 , Nov. 23, 1979;  49 FR 48712 ,
   Dec. 14, 1984, as amended at  54 FR 39740 , Sept. 28, 1989;  56 FR 64874 ,
   Dec. 12, 1991;  62 FR 18928 , Apr. 17, 1997;  65 FR 60877 , Oct. 13, 2000;
    67 FR 63289 , Oct. 11, 2002;  72 FR 35195 , June 27, 2007;  73 FR 25497 ,
   May 6, 2008;  78 FR 50345 , Aug. 19, 2013;  80 FR 25608 , May 5, 2015]

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