Sec. 22.657  Transmitter locations.

    The purpose of the rules in paragraphs (a) and (b) of this section 
is to define the areas in which the 470-512 MHz channels are allocated 
for public mobile use. The purpose of the rules in paragraphs (c) 
through (f) of this section is to reduce the likelihood that 
interference to television reception from public mobile operations on 
these channels will occur. The protected TV station locations specified 
in paragraphs (d), (e)(1) and (f) of this section are the locations of 
record as of September 1974, and these do not change even though the TV 
stations may have been subsequently relocated.
    (a) Base transmitter locations. Base transmitter locations must be 
within 80 kilometers (50 miles) of the designated locations in this 
paragraph. Mobile transmitters must not be operated at locations more 
than 129 kilometers (80 miles) from the designated locations in this 
paragraph.

------------------------------------------------------------------------
                                                                  W.    
                  Urban area                    N. latitude   longitude 
------------------------------------------------------------------------
Houston, TX...................................  29 deg.45'2             
                                                         6'  95 deg.21'3
                                                                      7'
New York, NY-NE NJ............................  40 deg.45'0             
                                                         6'  73 deg.59'3
                                                                      9'

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------------------------------------------------------------------------

    (b) Mobile area of operation. Mobile transmitters must not be 
operated at locations more than 48 kilometers (30 miles) from all 
associated base stations.
    (c) Protection from intermodulation interference. Base transmitter 
locations must be at least 1.6 kilometers (1 mile) from the current main 
transmitter locations of all TV stations transmitting on TV channels 
separated by 2, 3, 4, 5, 7, or 8 TV channels from the TV channel 
containing the frequencies on which the base station will transmit. This 
requirement is intended to reduce the likelihood of intermodulation 
interference.
    (d) Adjacent channel protection from mobile transmitters. Base 
transmitter locations must be at least 145 kilometers (90 miles) from 
the applicable protected TV station locations specified in this 
paragraph. This requirement is intended to provide a 0 dB minimum 
desired to undesired signal strength ratio at the Grade B contour of an 
adjacent channel TV station.

------------------------------------------------------------------------
                                       Protected TV station        TV   
Mobile transmitter frequency range           location            channel
------------------------------------------------------------------------
470-476 MHz.......................  Lancaster, PA 40                (15)
                                     deg.15'45' 76 deg.27'49'.          
476-482 MHz.......................  Scranton, PA 41 deg.10'58'      (16)
                                     75 deg.52'21'.                     
------------------------------------------------------------------------

    (e) Co-channel protection from mobile transmitters. Base transmitter 
locations must be at least the distance specified in paragraph (e)(2) of 
this section from the applicable protected TV station locations 
specified in paragraph (e)(1) of this section. This requirement is 
intended to provide a 40 dB minimum desired to undesired signal strength 
ratio at the Grade B contour of a co-channel TV station.
    (1) The protected TV station locations are as follows:

------------------------------------------------------------------------
   Mobile transmitter frequency range     Protected TV station location 
------------------------------------------------------------------------
470-476 MHz............................  Washington, DC 38 deg.57'17' 77
                                          deg.00'17'.                   
476-482 MHz............................  Lancaster, PA 40 deg.15'45' 76 
                                          deg.27'49'.                   
------------------------------------------------------------------------

    (2) The required minimum distance depends upon the effective 
radiated power (ERP) of the most powerful mobile transmitter(s) in the 
system:

------------------------------------------------------------------------
                                                      Minimum distance  
             Mobile unit ERP (watts)              ----------------------
                                                   Kilometers    Miles  
------------------------------------------------------------------------
60...............................................         193      (120)
50...............................................         185      (115)
25...............................................         177      (110)
10...............................................         169      (105)
5................................................         161      (100)
------------------------------------------------------------------------

    (f) Co-channel protection from base transmitters with high antennas. 
This paragraph applies only to base transmitter locations in the New 
York-Northeastern New Jersey urban area that utilize an antenna height 
of more than 152 meters (500 feet) above average terrain. The distance 
between the location of such a base transmitter and the applicable 
protected TV station location specified in this paragraph must equal or 
exceed the sum of the distance from the base transmitter location to the 
radio horizon in the direction of the specified location and 89 
kilometers (55 miles--representing the distance from the main 
transmitter location of the TV station to its Grade B contour in the 
direction of the base transmitter). The distance to the radio horizon is 
calculated as follows:
[GRAPHIC] [TIFF OMITTED] TR17NO94.009

where

d is the distance to the radio horizon in kilometers
h is the height of the antenna center of radiation above ground level in 
meters


------------------------------------------------------------------------
    Base transmitter frequency range      Protected TV station location 
------------------------------------------------------------------------
470-476 MHz............................  Washington, DC 38 deg.57'17' 77
                                          deg.00'17'.                   
476-482 MHz............................  Lancaster, PA 40 deg.15'45'' 76
                                          deg.27'49'.                   
------------------------------------------------------------------------

    (g) The FCC may waive specific distance separation requirements of 
paragraphs (d) through (f) of this section if the applicant submits an 
engineering analysis which demonstrates that terrain effects and/or 
operation with less effective radiated power would satisfy the 
applicable minimum desired to undesired signal strength ratios at the 
Grade B contours of the protected TV

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stations. For this purpose, the Grade B contour of a TV station is 
deemed to be a circle with a 89 kilometer (55 mile) radius, centered on 
the protected TV station location, and along which the median TV signal 
field strength is 64 dBV/m. In any showing intended to 
demonstrate compliance with the minimum desired to undesired signal 
ratio requirements of this section, all predicted field strengths must 
have been determined using the UHF TV propagation curves contained in 
part 73 of this chapter.