Attachment TallahasseeFL_WTXLTV

This document pretains to SES-LIC-20090612-00724 for License on a Satellite Earth Station filing.

IBFS_SESLIC2009061200724_716462

                                                       du Treil, Lundin & Rackley, Inc.
                                                                                     Consulting Engineers


                                                               Radiation Hazard Statement
                                                                              Sheet 1 of 3




                         ENGINEERING STATEMENT
                  RADIO FREQUENCY EXPOSURE EVALUATION
                     TEMPORARY FIXED EARTH STATION




               This Engineering Statement was prepared on behalf of WTXL-TV License
LLC, in support of an evaluation of the radio frequency (RF) environment in the vicinity
of the antenna of a temporary fixed earth station to be employed for satellite news
gathering (SNG). This statement details compliance with Section 1.1307(b) of the FCC
Rules concerning human exposure RF energy. This statement also details the RF safety
work rules for the safe operation of the proposed SNG facility.

Background

               The proposed facility will transmit in the Ku Band with a maximum EIRP
of 66.2 dBW. The facility employs an Advent Communications model Newswift 1.5M
1.5-meter aperture antenna, which is mounted on the rear roof of a cargo van. When
operational, the antenna center of radiation is located 4.1 m above ground.

Calculated RF Exposure Levels

               Calculations of RF exposure were conducted pursuant to the FCC’s OET
Bulletin No. 65, Evaluating Compliance with FCC Guidelines for Human Exposure to
Radiofrequency Electromagnetic Fields. Personnel in proximity of the transmitting
antenna will be located inside the vehicle or around the outside of the vehicle at ground
level. Work rules, further detailed below, prohibit personnel to be on or near the roof of
the vehicle when the antenna is operational.


                                                      du Treil, Lundin & Rackley, Inc.
                                                                                   Consulting Engineers


                                                             Radiation Hazard Statement
                                                                            Page 2 of 3



                All areas near the antenna, inside the vehicle, or about the vehicle at
ground level, are within the near field region of the antenna. Using Equation 13 of OET
Bulletin 65, the maximum near field, on-axis, power density level in the main beam of
the antenna is calculated as follows:

                             16ηP
                    S nf =
                             πD 2

                   where,

                       η = aperture efficiency      = 0.66
                       P = power fed to antenna     = 125,000 mW
                       D = diameter of antenna      = 150 cm

                    and, therefore,

                    Snf = 18.7 mW/cm2.

At one antenna diameter distance (1.5 m) off-axis from the antenna main beam, the
power density level would be at least a factor of 20 dB less than the equivalent value
calculated in the main beam.* This gives an RF energy level of less than 0.19 mW/cm2 at
2 m above ground around the vehicle. Furthermore, RF energy levels at locations within
the vehicle will be well attenuated below this level by the metallic skin of the vehicle.
While electromagnetic wave diffraction will occur off the edges of the vehicle the
diffraction levels will be attenuated significantly below the incident RF levels.




*
    See ¶2 on Page 31 of OET Bulletin No. 65.


                                                      du Treil, Lundin & Rackley, Inc.
                                                                                  Consulting Engineers


                                                              Radiation Hazard Statement
                                                                             Page 3 of 3




               The FCC maximum permissible exposure (MPE) levels for the 14,000-
14,500 MHz (Ku Band) are 5 mW/cm2 for occupational/controlled environments and
1 mW/cm2 for general population/uncontrolled exposure. Thus, RF energy levels within
and about the SNG vehicle at ground level will be well below the FCC MPE for general
population / uncontrolled environments. Therefore, the proposed facility meets the
requirements of Section 1.1307(b) concerning human exposure to RF energy.

Work Rules for Control of RF Exposure

              All personnel must adhere to the following work rules for compliance with
the FCC guidelines for human exposure RF energy during the operation of the SNG
vehicle.

       1.   No personnel shall be on the roof of the SNG vehicle during the operation of
            the transmitting antenna.
       2.   All personnel shall remain inside the SNG vehicle or at ground level around
            the vehicle during the operation of the transmitting antenna.
       3.   No human beings shall be located within a forward distance of 607 feet
            (185 m) on the axis of the main beam of the transmitting antenna during its
            operation.




                                     Louis Robert du Treil, Jr., P.E.
                                     du Treil, Lundin & Rackley, Inc.
                                     201 Fletcher Ave.
                                     Sarasota, Florida 34237
                                     (941)329-6000

                                     June 11, 2009



Document Created: 2009-06-11 15:08:44
Document Modified: 2009-06-11 15:08:44

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