An Investigation  of Radiofrequency  Radiation
     Exposure Levels on Cougar Mountain
              Issaquah,  Washington
                 May  6-10,  1985
                    Prepared for the
             Office of Science and Technology
            Federal Communications  Commission
      through Interagency Agreement RW27931 344—01 —0
                 Electromagnetics Branch
               Office of Radiation Programs
            U.S. Environmental Protection Agency
                    P.O.  Box  18416
                Las Vegas, Nevada 89114
                     December 1985

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                              EXECUTIVE SUMMARY


     During May  1985,  the Electromagnetics Branch  (formerly the Nonionizing
Radiation Branch)  of the Environmental  Protection  Agency's  (EPA)  Office of
Radiation   Programs   (ORP)   conducted  a   radiofrequency   (RF)   radiation
investigation on Cougar  Mountain,  Washington,  in response  to  a request from
the  Federal  Communications  Commission   (FCC).   EPA  found  that  FM_...rad.io
broadcast  antennas  are  the  only  significant  sources  of  RF  on  Cougar
Mountain.   The  majority   of  EPA's   measurements   were  made  at  publicly
accessible  locations relatively far  from  FM  antennas,  i.e.,  at  distances
greater  than  100  meters.   The  measured  values  are   relatively  low  when
compared   to    the    limits   developed   by    various   standards-setting
organizations.  These limits fall  into the  range  100 to  1,000 microwatts per
square centimeter (yW/cm2) for FM radio frequencies.

     Two  types   of  results  are  presented, spatially   averaged  values  and
maximum   localized   values.   The  spatially  averaged  values   are   most
representative of an  individual's  typical  whole-body exposure.   The  maximum
values  are  normally  associated  with  areas of limited  extent  wherein  only
partial-body exposures might occur.   The  greatest  spatially  averaged  power
density  measured in  a  publicly  accessible location  is  700  yW/cm2  within
25 feet  of  a  tower  which  supports  an  FM  antenna.  Near residences,  the
greatest  spatially  averaged power  density found was  117  yW/cm2.   Measured
localized maximum power  densities  in  two publicly  accessible  areas exceeded
the  1,000 yW/cm2  ANSI  radiation  protection   guide  adopted  by  the  FCC.
These  include  areas  near   the  unfenced   KMGI/KZOK/KMPS  tower,  where  one
measurement exceeded  2,000 yW/cm2, and  locations  near  one residence  where
a  maximum  of  2,350  yW/cm2  was  found.    Indoors,  highly  localized  power
densities  reached  350  yW/cm2,  while  spatially  averaged  values  did  not
exceed 23 yW/cm2.

     Because power density  values  are likely  to  increase with  height  above
ground on Cougar Mountain,  and because the  conducting objects  normally found
in  structures  tend   to  enhance  ambient  RF   fields,   the  siting  of  new
multistory dwellings near the  high power antennas on Cougar  Mountain  should
be  approached  with  care.   Also,   cooperation  among  broadcasters  will  be
needed to prevent tower  climbers  in the Ratelco  North  Lot from  exposure  to
power densities exceeding the ANSI  radiation protection  guide.

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                              TABLE OF CONTENTS
Executive Summary  	    i
Table of Contents  	   i i
List of Tables and Figures	  iii
Background 	,..    1
Equipment 	    1
Procedures 	..    3
Results and Discussion 	"..    6
Summary	   10
Tables 	   13
Fi gures 	   20
References 	   36
Glossary	   37
Appendix - Equipment and Calibration Information 	   38
                                     n

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                               LIST OF TABLES

 1.  Transmission Frequencies on Cougar Mountain by Tower Number 	   13
 2.  Narrowband Measurements and Broadband Comparisons 	   17
 3.  Indoor Measurement Data 	   18
                               LIST OF  FIGURES

 1.  Map of Seattle Area Showing Location of Cougar Mountain 	   20
 2.  Computer Plot of Calculated Power Density Values
     for Cougar Mountain 	   21
 3.  Cougar Mountain Spatially Averaged Power Density Values
     and FOISD/Holaday Comparisons 	 Attachment
 4.  Site 2 FM Spectrum 	   22
 5.  Site 3 FM Spectrum	   23
 6.  Site 4 FM Spectrum	   24
 7.  Site 5 FM Spectrum	   25
 8.  Site 6 FM Spectrum	   26
 9.  Site 7 FM Spectrum	   27
10.  Site 8 FM Spectrum	   28
11.  Site 9 FM Spectrum	   29
12.  Site 7 Wideband Spectrum	   30
13.  Probability Plot for Cougar Mountain Spatially Averaged
     Power Density Values in Accessible Areas 	   31
14.  RATELCO North Lot Maximum Values	   32
15.  Probability Plot of Power Density Values at All Measured
     Points Inside RATELCO North Lot 	   33
16.  RATELCO KUBE Enclosure Maximum Values 	   34
17.  Maximum Values Near KMGI/KZOK/KMPS Tower 	   35
Al.  Holaday Model 3001 Electric field Calibration in
     FM Frequency Band 	   39
A2.  Narda Model 8616 (8631 Probe) Magnetic Field Calibration
     in FM Frequency Band 	   40
A3.  NanoFast Model EFS-2 Fiber Optic Isolated  Spherical  Dipole
     Antenna Factor 	   41
A4.  Antenna Factor Graph for the Tunable Dipole with 20 Feet
     of RG-55 Cable 	'..   42
A5.  AEL Model APX 1293 Crossed Log Periodic Antenna Factor
     for 1 to 13 GHz 	   43
A6.  Watkins Johnson Model  WJ 8549 Antenna Factor for 1-18 GHz  	   44
                                     m

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                AN INVESTIGATION OF RADIOFREQUENCY RADIATION
                     EXPOSURE LEVELS ON COUGAR MOUNTAIN
                            ISSAQUAH, WASHINGTON
                                MAY 6-10,  1985
Background
     Cougar Mountain  lies  approximately 12  miles east-southeast  of Seattle
with its summit 1400  to  1500 feet above Seattle  (Figure  1).   The mountain's
elevation above Seattle  has  made it  a  popular location  for  broadcasters to
place  their  antennas.   Twenty-two   towers   sit  atop  the  mountain  today,
supporting  10  FM antennas,  several  microwave  point-to-point  dishes,  and a
myriad of  o.ther  low-power  communications  antennas  (Table 1).   Twenty years
ago, when few residents  and  fewer antennas resided  on Cougar Mountain, there
was little  concern  about the levels of electromagnetic  radiation there.  As
more  people  moved  to   the  mountain  for  its magnificent  views,  as  more
broadcast   and  communications  companies  chose  Cougar   Mountain  for   its
advantageous position over the  Seattle area,  and as questions  arose  in the
popular and scientific  press about  the biological effects  of radiofrequency
(RF)  radiation,   many  residents  developed   a concern   about  the  possible
hazards of  being so close to an  "antenna  farm".  They wrote  to  their county
government,  to   the   Federal  Communications  Commission  (FCC),   to   the
Environmental   Protection    Agency   (EPA),   and   to  their   Congressional
representatives seeking  information  on  the  levels  of RF  radiation  on  the
mountaintop,  inquiring  about  the   possibility  of  any  associated  health
consequences,  and  requesting relief  from  the  addition  of more  antennas  to
the area.

     The FCC responded  to  citizens'  concerns  by  requesting  an EPA  study of
the RF levels on Cougar  Mountain.  The  Electromagnetics  Branch (formerly the
Nonionizing Radiation Branch) within the  EPA Office of  Radiation  Programs,
assisted  by personnel  from  the  FCC  Seattle  and   Washington,  DC  offices,
conducted the study during the  week  of May  6, 1985.  This report  describes
that study  and is provided by EPA to the  FCC under the terms  of Interagency
Agreement number  RW27931344-01-0.

Equipment

     The  strength  of  RF   fields   is  commonly  measured  using  broadband
isotropic  electric  or   magnetic  field  meters,  or  antennas  connected  to
tunable field  strength  meters.   Broadband  equipment is  used  to provide  an
indication  of  the  total RF  field   at  a  point  while  narrowband  equipment
provides  detailed  information   on   the   RF   intensity   at   any  particular
frequency.  This  study employed  both  types  of equipment.

     The  Fiber  Optic   Isolated  Spherical   Dipole   (FOISD)   was   used   for
narrowband  or frequency  specific  measurement  of  frequencies  up to  700  MHz.
The FOISD's small  size  (a  sphere  about  10   cm  in  diameter)  allowed us  to
calibrate it in a small  calibration  apparatus  in  our  facility  at frequencies
of major interest  before leaving for Seattle.  The FOISD's size  and  the  fact
that it  does .not need  to  be adjusted  to-each  frequency individually  also

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make  it  far more convenient  to  use in  the  field than  the larger  and more
cumbersome  half-wave  tuned  dipoles,  which  require  readjustment  at  each
frequency   of   interest.   The   FOISD  was  calibrated   in   a   transverse
electromagnetic  (TEM)  cell  in the Electromagnetics Branch  laboratory  in the
Las  Vegas  Facility.   The  report,  An  Automated  TEM Cell  Calibration  System
(1), describes this calibration facility.

     Between 700 and  1000 MHz,   a  Singer Model  DM-105A-T3 half-wave., .tuned
dipole was  used.  We  have  experimentally determined  the  antenna  factor for
this narrowband Singer system.

     Above  1000 MHz  we used an AEL  Model  APX-1293  crossed log  periodic
antenna  (1-13  GHz),  and  a Watkins Johnson  Model  WJ 8549  vehicle-mounted
omnidirectional  bicone antenna  (1-18  GHz).  We  determined the  calibration
factor   for   the   AEL    and    Watkins   Johnson    antennas    based    upon
manufacturer-supplied  data  for the  frequency range that would be  of primary
interest to us  as  we  used that  antenna.  For  example,  our  antenna  factor
curve for the  Watkins  Johnson omnidirectional bicone  antenna  (see Appendix)
is based upon a 2dBi gain  figure  supplied by  Watkins  Johnson  for a frequency
of approximately 15 GHz,  a frequency  which  is within  the range  (2-18 GHz)
for which we used that antenna.

     All these  antennas  were linked  to  a  Hewlett  Packard   8566A  spectrum
analyzer  to   measure   RF   electric  field  strengths.    The   analyzer  was
interfaced  to  a  Hewlett Packard  9845B desktop computer which  controlled the
analyzer, processed, and  stored  the frequency-specific electric field  data.
We used  the  internal   calibrator  in  the spectrum  analyzer   to  verify  the
calibration of the  analyzer itself  in the  field.   We verified the  accuracy
of the  internal calibrator signal  with  a power  meter upon  our  return  to
Las Vegas.   All  calibrations  referenced  in this  report are traceable to the
National Bureau of Standards.

     Upon arrival at Cougar Mountain, we  checked the response  of the Holaday
3001 broadband electric field strength meter and the Narda 8616 (8631  probe)
broadband magnetic  field  strength  instrument.   It was   apparent  that  the
Narda would be of limited usefulness on  Cougar Mountain because of a serious
zero-drift  on  its  lowest   (most   sensitive,  i.e.,  0  to 200yW/cm2)  scale  -
the scale where most of  the Cougar  Mountain  values would  be read.   However,
the  Narda's next scale  (0 to 2000 uW/cm2)  did» not  exhibit   a significant
zeroing problem and was used in a few of  the higher  exposure sites.

     The Holaday meter does not suffer from  a zero drift  problem  because  it
self-zero's many times  each  second.   However,  the  Holaday  fulfilled  its
manufacturer's   predictions  that   it would  overrespond  in the  presence  of
multiple FM fields of  similar intensity.   Despite these problems,  we decided
to use the  Holaday  because its stability  (i.e.  lack  of zero  drift) allowed
us to compare  it to more  accurate,  narrowband  FOISD values at  several  sites
and  power   densities.    For  further  information  on  calibrations  and  the
equipment used  in this  study,  see the Appendix.

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Procedures

     Two months before the study, the  Puget  Power  Company sent us a notebook
of  maps,  photos,  contacts,   and very  detailed  information  concerning  the
engineering  characteristics  of  antennas  on  Cougar  Mountain.   Puget  Power,
which owns two towers on Cougar  Mountain,  had gathered  information on  the RF
environment  there   in  response  to   inquiries  from   the  residents.   The
information contained in the Puget Power book saved  us  days of long-distance
telephone  investigation.   After verifying   items  of  interest  and  adding
details that we  learned  from the FCC,  FM  station  engineers,  and  the  owners
of  the  towers, EPA  predicted  the maximum  RF levels that all  the  antennas
were likely to create on  the mountaintop.    (The modeling  techniques we used
are described  in  reference 2.)   These calculated power density values shown
in  Figure 2, helped  determine  the scope of  the  investigation,  and suggested
areas where detailed mapping of  fields would be warranted.   The contours on
Figure 2 are located at the greatest distance from the  towers at which power
density  values  as   high  as  the stated   values  were  predicted  to  exist.
According to the  model,  much of the  mountaintop would be above  100  pW/cm2
with a  few locations on  Cougar  Mountain  exceeding  1000 uW/cm2.  It  should
be  noted that  due to particular antenna characteristics,  the field  strength
does not decrease monotonically  with  distance from the antenna.   Therefore,
there can be multiple contours  for  a  single  power  density value.  Figure  2
displays  only  the   most  conservative  (i.e.,  furthest  from  the  antenna)
contours for the  three exposure values.

     Using the modeling results, we considered how we should investigate  the
mountaintop  in  order  to  present  the  most  complete  picture  of  the   RF
environment there.  We decided to collect  spatially  averaged  values  (typical
measurements which  exist over  a vertical  planar  area  of  about  70  square
feet)  and  maximum  values  (maximum measurement values  normally  associated
with areas  of  limited   extent  wherein  only  partial  body  exposures   might
occur)   both  outdoors and  indoors.   While  frequency specific  measurements,
using  the   dipole  antennas  and  the   spectrum analyzer,  provide  the most
detailed and most accurate information, the  size of the Cougar mountain area
and time constraints dictated  that  broadband meters be used to collect  the
majority of the data.

     In general  we  tried  to  obtain  spatially  averaged   or  typical   values
wherever people might be  located - inside and outside homes,  along  roads,
and even around fenced areas.  Because there were so many  locations at which
to  measure  such  spatially averaged values,  over 400,  we  used a broadband
instrument that  could  be handcarried  and  that  allowed  us  to collect data
rapidly.

     We searched  for maximum values  in order  to characterize  some  areas more
thoroughly.   Areas that  we  believe  warranted  this  extra   attention  included
residences and locations close  to FM  antennas.  We  used  the  same broadband
meters   to  find maximum  power  density  locations  that  we had  used  for  the
collection   of   spatially   averaged   values   because   those   meters   are
lightweight, and  can be quickly  and  easily  maneuvered to  search for peak
values.

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     We  used   narrowband   equipment   at   several   sites  to  determine  the
contribution of each  FM  station  to the total power density  at  a given point
and  to  estimate   the error  associated  with  the  less accurate  broadband
measurements.   We  chose   sites  for  narrowband  measurements  which  were:
(a) near  homes,  since  narrowband  readings  permit more  accurate  exposure
assessments  and allow the development of correction  factors  for  the more
numerous  broadband  data;   and  which  were  (b)  at various  distances  from
clusters  of FM antennas.   We chose  several  distances from  the FM_towers
because  we  wanted to  learn the  actual  exposure values  at  those points  in
order  that  we  could  assess  the  broadband instrument errors  under different
combinations   of   FM  signal   strengths.    The  Hol'aday  manual   predicts
over-responses  in the  presence   of  multiple  signals  which  are  strong  and
approximately equal in magnitude.

     • Frequency Specific Electric Field Data

     Frequency specific data enhance the  usefulness of  any study not only by
providing  accurate standard  values  against  which broadband   data  can  be
evaluated,  but  also by  identifying the contribution of  emissions  at various
frequencies to  the total power density  at a point  in  space.   The  approach
for these measurements was (a)  to seek sites  at various distances  from  the
different frequency band antennas  on the  mountain,  (b)  to sample  at  a  group
of sites where a wide range of field intensities existed, and  (c)  to measure
the  fields  near  residences.   Eight  sites  were chosen.  All   but  one  are
accessible  to  the public.   A quick  survey with the Holaday would  locate  a
point  in  space where the  field  was strong for  that  particular  site.   The
FOISD  was  then   placed   at  that  point  in   space,   and  collection   of
frequency-specific data commenced.

     The  computer processed  electric   field data  from  three  orthogonally
aligned  FOISD  measurements at each  site, and  saved  the resulting  spectra.
After  each  set  of three  FOISD measurements, the FOISD  was  removed  from  its
gimbals.  We then  centered the Holaday probe  in  the gimbals  and  measured  the
field through a 360" rotation of the probe about the axis of  its handle.   An
average field  intensity  from  that rotation was  recorded for  comparison with
the  FOISD  value   for  the  FM band.    Every value  was  corrected  for  the
frequency response of the  instrument  and  converted to  plane wave  equivalent
power  density  units.   The  power  density  comparisons  are listed in  Table  2
for the  eight  sites.   Figure 3  (the attached  large  fold-out map)  displays
the  locations  of  the  comparison  sites  and  identifies  each with its  site
number inside  a triangle.   (Note that  in  Table 2 and  Figure  3 there  is  no
comparison  site No. 1.)  The other values  on Figure 3  are the power  density
values which are discussed  in the next  section of this report.

     Magnetic  field  data  were  collected  to  determine  if  electric  field
values  could  be   used   to reliably  predict  equivalent  plane  wave  power
densities.  We used the  Narda 8631 broadband magnetic  field probe for  these
measurements.    At  three  sites where the  RF fields were great enough,  we
measured the maximum  magnetic field in the  vicinity of the  site where  the
electric field  values were  taken, but we  were unable to  obtain  reliable
values at 5 other  comparison sites due  to  the zero drift problem.

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     After collecting the  FM  band  data with the FOISD, we  returned to three
of  the  comparison points  to  collect information  on  the electric  fields at
non-FM  frequencies.   We  collected  data at one  site  (No.  10),  which  was not
an  FM comparison  point, because  it was  near  residences  and  it overlooked all
the  antennas  on the mountaintop.  Table  2 lists  these  data by  site number
and  by  the   instrument   used  to  make  each  measurement.    Some  non-FM
frequencies  were  sampled  by  taking  three  orthogonal  FOISD  measurements.
When half-wave tuned dipoles were used, we oriented them  in the azimuth. ..such
that  the  field  produced  the  greatest  amplitude signal   on  the  spectrum
analyzer,   and   then   collected    data   from   horizontal   and   vertical
orientations.   To collect data  with  the  crossed  log  periodic  antenna,  we
directed  it  at a tower which  supported antennas  of  interest and  which  was
visible  from  the measurement point.    To  redirect  the antenna  toward towers
which were not visible  from  the measurement point, we  took angles  from our
maps  and  rotated  the  antenna  accordingly.   At   higher  frequencies  we
sometimes sampled only a  single  polarization.   In  some cases we  were forced
to  collect peak  values  rather than  average, because  of  the duty cycles  and
low  powers of  the transmitters.   The omnidirectional  antenna samples in the
horizontal plane, hence it requires  no  azimuthal orientation.   It is mounted
in a fixed vertical position on our  vehicle and  thus  collects data from only
vertically polarized fields.   Unlike the FM band  data which were collected
at  a height  of 7  feet  or less because we  could  not reach higher with  the
broadband probe  or place  the  FOISD  higher  on  its tripod,  the  non-FM  band
data were collected  at  heights which  ranged  between  5 and 10 feet  because
the non-FM band antennas were placed  atop  our truck.

     •  Broadband Spatially Averaged Values

     Our intention was to find spatially averaged  values  in areas accessible
to  the   public  (i.e.  in   areas  that  were not  fenced).   Although  we  had
considered taking data at  intersecting gridpoints  on  the mountain,  the dense
vegetation over  much  of the area did  not allow us  to establish  gridlines,
much less  physically move to  intersection  points.   So we collected  data
every 20 to  25 feet along  each  road  in  the  area,  around  the  exterior  of
fenced  areas,  and  near  homes.   (One  exception  to  this  plan was  that values
were taken just  inside  the Ratelco  North  lot fence in  a  defoliated  area  in
order to speed data collection.)  The  areal  extent  of  the Cougar  Mountain
survey was determined by  our ability  to  obtain on-scale  indication  of  the
ambient  field  strengths  on the  most sensitive  range of the* Holaday  meter
(the equivalent  of 1-2  uW/cm2).  At  each  measurement  point,  we  surveyed
over the point  in  a  vertical  plane  about  7  feet high by 10 feet wide  with
the Holaday probe.  We  deliberately  avoided  locations where the  field might
be  affected by nearby conducting objects  (see  "Maximum  Values"  below).   We
recorded our best estimate of the  spatially  averaged  square of the  electric
field  value  (V'/m2)  throughout  the   plane   that was   surveyed.    Through
repeated  measurements  at  the, same  location,   but at  different  times,  we
became    confident   that   our   estimated   spatial   averages   were   within
approximately 30 percent of the  actual  spatially averaged  value.

     •  Maximum Values

     Despite  the  fact  that  they may be- quite  localized,  maximum  power
density  values   are   important   for   hazard   assessment   and   compliance

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monitoring.   Maximum  values are  of  two varieties.   The first  results from
unperturbed  fields  in  space  which  happen  to  sum  to  a high  value.   These
would  be  at  points  of  standing waves.   The  second  variety  is  caused  by
perturbation  of  an  electromagnetic field by  a conducting object.   This can
dramatically  enhance the  field  intensity over a small  area.   We set  out  to
locate the maxima by searching  near  the strongest sources of RF energy (the
FM antennas)  and by searching  for field perturbing situations  in areas that
are likely to be frequented by people.   In some cases  those  two criteria-led
us to the same area.

     Near most  of  the  FM antenna's we  recorded maximum  values  as  we  moved
along the four  compass  radials  (referenced  to  true  North)  from  the  base  of
the tower.   At  ten-foot  intervals from  the  base of  the tower,  we searched
for the  maximum field  value  within  our reach using  the Holaday  broadband
instrument.   The elevated levels  inside the  North  Ratelco  lot  called  for  a
more exhaustive  series  of measurements,  while the relatively low levels and
dense  vegetation near  the KQKT  tower  argued against   radial  measurements
there.  After completing  the radials,  we searched in  areas where the radial
data  suggested   high  field  strengths  would  be  found,   and  recorded  those
values.

     The approach for  areas that would be frequented by  people  was  to survey
the area  generally  but  emphasize locations near  conducting objects  such  as
fences, swing sets, etc.   We did  not  search  for maximum values that  might
have occurred near  transient structures like automobiles.

     • Indoor Measurements

     The  purpose of this study  was  to estimate  the  potential  for  human
exposure  to  RF  fields  on Cougar Mountain.   Measurements inside  residences
were  therefore   included.   Three  homes  near  the  Ratelco  North  lot  were
surveyed, room by room.  In each house, spatially averaged as well  as maximum
values were  recorded.   The  residents  were helpful, not  only by  allowing  us
access, but  also by directing us  to  locations at which  previous  surveys had
found  elevated  field  intensities.    Interior  electric  field  data   were
collected with the  Holaday.

Results and Discussion

     The data collected in  this  study  are primarily electric field strength
values supplemented with  a few  magnetic field  strength measurements.  The
data that we report, however,  are in power density  units of microwatts per
square  centimeter   (uW/cm2).    We converted   the   electric  field   strength
values to power  density values, assuming equivalent  plane  wave  conditions.
All the values reported  here are corrected for the frequency response  of the
instrument.

     • Frequency Specific  Values

     Table 2 displays  the  frequency specific  measurements  for  9  sites  on
Cougar Mountain.  The corresponding  FM  band  spectra  and individual  station

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power density  contributions  are shown in Figures  4  thru 11.   The data show
that power densities from  FM band sources far exceed  those  from non-FM band
sources.   Figure  12,   a  spectrum   taken   near  site  7,   highlights  this
distinction  between  FM  (88   to 108  MHz) and  other  frequency bands.   The
spectrum  plot  in  Figure 12,  in  conjunction with the  data for  Site  7  in
Table 2,  show  that   the  contribution   to   power  density  from  frequencies
outside the  FM band  constitutes only one to two hundredths of a  microwatt,
or less than  one percent  of the  FM power density at this  site.   Hea.c.e. the
non-FM  band  sources  contribute such  low power  densities that they  may  be
neglected for practical purposes.

     A more subtle distinction  than that  between FM  and  other  frequencies  is
that  between  the  FOISD and  Holaday  values at  the  8  comparison  points
(Table 2).  The ratios of the FOISD to the Holaday values range from 0.53  to
1.14  for   the  sites  we  sampled.   Using the  FOISD  as  our  standard  for
measuring field  strength,  these data imply  that the Holaday typically read
high and  its values  should be multiplied by some  factor to correct  for its
multiple-frequency response.   Unfortunately,  the only  way  to  know  what
factor  is appropriate  for  a  particular  point  is to take frequency specific
data at that  point.   Of course,  if frequency specific  data were available
for every point, there would  be no need for Holaday readings.   The dilemma:
very  accurate  data  that  require  an  inordinate  collection   time  or  less
accurate  data  which  can be   collected  in a reasonable  period  of time  and
whose error range can be estimated.  We  opted for the latter.

     Each  of the Holaday  values  presented   in this  report,  while corrected
for the frequency  response of  the meter, should  nevertheless  be  considered
to represent  a  range  of  values  whose   boundaries  are about  0.53 and  1.14
times the  stated value.   This  correction is  necessary  to  account for  the
Holaday's   erroneous  response  in  the  presence  of  multiple,   strong,  and
approximately equal  strength signals.  Realizing  that the  Holaday's  error,
and hence the appropriate correction factor,  can change  over short distances
as the  contributions  from  various  antennas  change,  we  nevertheless  feel
comfortable using a particular  correction factor over  a  limited area (radius
of 50' to 100')  centered on  the actual  comparison  site.   We arrived  at this
conclusion after comparing the  FOISD/Holiday ratios at  sites  8 and  9.   The
comparison values are similar at these two nearby sites.

     The  Narda  magnetic field  meter  operated well  at  three   of  the  sites
where the Holaday  and  FOISD were  used  (see  Table 2).   At  these  sites,  the
equivalent  plane  wave  power  density   that  corresponds  to   the  measured
magnetic  field   (corrected    for   the   meter's   frequency   response)   is
approximately equal  to  that  predicted by the  electric field value  obtained
with  the FOISD.  The ratios  of  the FOISD  to  Narda  values at the three sites
are 0.97, 1.20,  and  1.09.    These  data  indicated to us  that electric  field
values could be  used to  reliably  predict power densities on Cougar  Mountain
in the absence  of measured  magnetic field values.

     •  Broadband, Spatially Averaged Values

     Figure  3   shows  the  spatially  averaged   power  densities  on  Cougar
Mountain as well as the  correction factors- for  the Holaday  which  were found

-------
at  various  points.   As  expected,  the  spatially  averaged  values  decrease
rapidly  as distance increases from  FM antennas.   Interestingly,  the values
are  far  lower  than  those predicted  by our  modeling.   We  attribute  this
discrepancy  to  three  causes.   First,  the  model  is  designed  to  avoid
underpredicting,  so some  overprediction is  likely.    Second,  the model   is
designed  for level terrain.   As one  moves  away from  the towers  on  Cougar
Mountain,  the distance  from the antenna  is  greater and  the  elevation angle
from the point to the antenna  is steeper  than  what  would be predictedJf. the
area  were  level.    Hence  the  actual  power  densities   are  lower  than
predicted.   Finally,  the  dense  vegetation  atop Cougar  Mountain  attenuates
the  RF  fields.   The  trees also help  to increase  the  inhomogeneity  of  the
field.   For  these reasons, the  ratio  of the  actual  power densities  to  the
calculated power densities can be anywhere from about one-twentieth to one.

     Figure  13  shows  a probability plot of the over-400 spatially averaged
values  which were  measured  on  Cougar Mountain where  the  equivalent power
density  exceeded 1-2  yW/cm2, the  practical  lower limit  of  detection  for
the  Holaday  instrument.   The  highest  of these  values  exceeded  700  yW/cm2.
Although there  are  many points that exceed  200  yW/cm2,  about  95  percent  of
the   values   are   less   than  200 yW/cm2,   88  percent   are   less   than
100 yW/cm2,  and  75 percent  are  less  than  50 yW/cm2.   Although  the  method
of  data  presentation  used  is  sensitive to  the  selection  of  measurement
locations,  Figure  13  provides  a  convenient  means  for  summarizing  the
spatially  averaged  data.   In  off-road  areas,  we checked the fields  in  the
pasture to the east of the Ratelco North  lot and in the park  at the old Nike
site.   In  the pasture, the  values were remarkably uniform  at about  45-50
yW/cm2.    At  the  park,   common  values  were  about   2  yW/cm2,   with   the
highest  levels   routinely  reaching  no  more   than  5  yW/cm2.   In, the  most
uniform field we found, the variability  over the vertical plane surveyed was
a factor of 4 from  the  greatest  to  the lowest  value.    It was not  unusual  to
see  a factor  of  2  in  horizontal  variability and  a  factor of 8  to  10
vertically.

     To  place  these data  in  perspective,  it  is  helpful to  know that the
least stringent  standard  in  existence  for  FM  frequencies  is  1000  yW/cm2,
published  by  the American National Standards  Institute  (ANSI) and recently
adopted by the  State  of New  Jersey  and triggering environmental  reviews  by
the  FCC.   The  National  Council  on Radiation and Measurements   (NCRP) has
prepared a draft standard at  the  200 yW/cm^  level  (3).  The  International
Radiation  Protection  Association  (IRPA), the State  of  Massachusetts, and
Multnomah  County  Oregon   have  all  adopted   the  same  limiting  value for
exposures  in  the FM band  (200 yW/cm2).   The  City  of  Portland, Oregon, has
chosen  a  100  yW/cm2  limit  for  FM  frequencies within  its  borders.  EPA
estimates that the average power density  in urban areas  of the  United  States
is about  0.005  yW/cm2, with  fewer than  1  percent  of  the urban  population
exposed  to  levels  greater  than  1  yW/cm2  (4).   Figure  13  portrays the
Cougar Mountain  spatially  averaged  values,  several standards,  and EPA  data
on urban RF power densities.   It also shows that while  none of  the spatially
averaged values  at measured locations  in  accessible areas on  Cougar Mountain
exceeds   1000   yW/cm2,   about  5  percent   exceed   200  yW/cm2   and   about
11 percent exceed   100  yW/cm2.   However,  one  of  the  spatially averaged
values found  just  inside  the fence  at the Ratelco  North  lot does  exceed
1000 yW/cm2-   •

                                     8

-------
     • Maximum Values

     Figure 14 locates maximum values that we  found  along several radials in
the fenced  Ratelco North lot.   Several  of the values  inside the  North lot
exceed 1000  yW/cm2, with a few surpassing  even  2000  yW/cm2.   In  order to
obtain a  general  impression of the  RF  environment  inside the  Ratelco North
lot, we combined  the maximum values (Figure 14) with the spatially averaged
values  (Figure  3)  and   plotted  the  resulting  collection  of  data	on -a
probability scale.  Figure  15  is the result,  and shows that in  the mixture
of maximum and spatially averaged values, a few percent of the  points exceed
2000 yW/cm2   about 20 percent   exceed  1000 yW/cm2,   and  98  percent  exceed
100   yW/cm?-    After  correction   of   these   values   for   the   Holaday's
multiple-frequency  response,  the ANSI   limit  will   be   exceeded  inside  the
Ratelco North lot.

     The  levels  inside the  KUBE fenced  enclosure  (Figure 16) are  far lower
than those  inside Ratelco  North, with   maximum  values   of about 375  yW/cm2
along the radials.

     Moving to unfenced areas, just  outside the Ratelco North lot west gate,
(Figure  14)  are  two  locations where  the  Holaday  reading  approximated
1000 yW/cm2.  The  maximum value  in  the  area between  the  KUBE enclosure and
the North Ratelco  lot  (Figure  16)  was about 470  yW/cm2.  Near  the unfenced
KMGI/KZOK/KMPS  tower   (Figure  17),  power  densities  at  several  locations
approach   or  exceed  1000  yW/cm2,  with  one  nearly   1700 yW/cm2   and   one
exceeding 2000  yW/cm2.    It is   apparent  from  the data  in  Figures 14,  16,
and 17,  that  the power densities decrease  rapidly  with  increasing distance
from the  tower.

     The  search for maximum outdoor values  near residences was  concentrated
just east  of  the  Ratelco  North  site in  a backyard  play area  behind  the
Percival  residence, the  nearest residence  to  any of  the broadcast  towers.
On Figure 14  this play area is  located  about  100 feet east  of  the  eastern
fence of  the  Ratelco  North  Lot,  and due east  of  towers 4 and 5.   While the
spatially averaged  power density in this  area  was  about 117  yW/cm2,  the
greatest  unperturbed field value we  found corresponded  to  a power density of
about 350 yW/cm2.   In  perturbed  fields,  the values  were much higher.   Near
a fence,  the  power density rose to 1174 yW/cm2.  At  the end  of  the  swing
set the maximum  value  was about 1450 yW/cm2,  and near  the chinning bar the
equivalent  power  density  exceeded  2350  yW/cm2.   Despite  the  fact  that
these  perturbed  field values  are  very localized,  they  are real  and  can
result in relatively high partial body exposures.

     • Indoor Measurements

     Spatially averaged equivalent  power density  values for  the  interior of
three homes  near the Ratelco  North site ranged  from  negligible  values  to
23 yW/cm2.    However,   Table   3   shows  that   the   maximum,    apparently
unperturbed fields inside the homes  occurred in the bedrooms  along  the south
side of  the  Percival  residence and  were  approximately  300  yW/cm2.   These
values exceed all existing exposure guidelines  except  the  ANSI  radiation
protection  guide  level.    (While  it  is possible  that  these  fields  were

-------
"perturbed"  by  the house wiring  acting as an  antenna,  it  is  unlikely that
the  elevated RF fields are  due to 60  Hz  current  in  the house  wiring.  We
have  found  that   the  Holaday  does   not  respond  to  60  Hz fields  of the
intensity that  is  found  near common  electrical wiring.)   The metal  lamps in
the  homes  are  examples  of  conductive  objects near  which  elevated  fields
could  be  found.   The  highest  perturbed field  equivalent power  density was
352 uW/cm2  along  a curtain  rod  in  one   of   the  bedrooms  in  the  Sparks
residence.   Towel   racks,  metal  door  and   window  frames,  and  curtain  rods
proved to be  good  indicators of areas where the local electric  fields  "would
be elevated.

     • Miscellaneous

     At site  3  the Holaday meter did not   experience  the multiple-frequency
error evident at other sites, because  there was a single  dominant  FM  signal
at this point (24  dB  above  the next highest  peak).   The FOISD  and  Holaday
agreed very  well  in the  comparison  at this point,  their ratio  being  1.04.
The  Holaday  was   a  good  indicator  of  actual  field  strength   at  site  3;
therefore, we decided to  look at  the  FOISD  support  structure's  effect  on the
FOISD values  by using  the Holaday to measure  the  electric  fields with and
without the  support structure  present.  The  structure consists  of a  wooden
tripod topped by  a  10 cm diameter  flat metal  plate,  and  a metal  adapter
which supports a wooden post and  platform  on which the  plastic  gimbals sit.
The distance from the flat metal plate to the center of  the  FOISD antenna is
about 51 cm.  Data were taken  with this 51  cm structure both in place, and
removed.    The point of  measurement  in both  cases was  the center  of the
FOISD's  gimbals,   with the  FOISD  removed,  of course.   With  the  support
structure  in  place   the  Holaday  meter   read 330   V2/m2   (87.5   yW/cm2),
Without  that  structure  perturbing   the  field,  the  value  was  380  V2/m2
(100.8 yW/cm2).

     These  data suggest  that  the  FOISD   values,  and  also  the  Holaday's
multiple-frequency  correction factors,  should  be altered.   Using these new
data, the Holaday  correction multipliers would  range  from 0.61 to 1.31  over
the entire mountaintop.   However,  a  few considerations caution against  this
change.  First, when the  FOISD  was calibrated  at the Las Vegas facility,  it
was calibrated while resting  in  its gimbals.  Hence the effects of a part of
the  field-perturbing  structure  are   already  included  in  the   calibration.
Second, we  performed  this  check only  once  on  Cougar  Mountain,  in  part
because there were only  a few  sites  where the Holaday meter  corresponded
well  with the FOISD values, and in part because there  was no time to  pursue
the  question.  The Holaday  meter's  multiple-frequency  response  and  the
gimbals'  effect upon the  FOISD response underscore the  fact  that not  only
the Cougar Mountain RF environment,  but also  the techniques  by which  that
environment  might  be   measured  are  quite  complex.    We  will   study  the
influence  of the  FOISD  antenna  support  structure  in  the  Electromagnetics
Branch laboratory and during  future field studies.

Summary

1.   With  the exception  of  the data  collected  at  the nine  points noted  in
     Table 2, all  data in this  study were  taken using  a Holaday 3001  meter


                                     10

-------
     with  an electric  field  probe.   In  this document,  all  power density
     values  which were  derived  from the  Holaday  values,   incorporate the
     instrument's frequency  response  correction  and  have been  converted to
     units of equivalent  plane wave power density.  We  have  not altered the
     power  density  values to  correct for  the Holaday's  multiple-frequency
     error, but have  estimated the correction factor to be between 0.53 and
     1.14.   We  believe these  factors may  be used to  a  distance  of  50 to
     100 feet   from   the  actual   measurement   site    without   introducing
     significant error.

2.   Non-FM  band  antennas  are  insignificant  contributors   to  the  power
     densities  that  exist on  Cougar Mountain.   For  hazard  and  compliance
     purposes, FM antennas are the only significant sources on the mountain.

3.   Vegetation,  coniferous  trees  in particular, appears  to be  a  good RF
     radiation shield.

4.   The  greatest spatially  averaged  power  density  that   we  found  in  a
     publicly accessible  area  was about  700  yW/cm2-   No  spatially averaged
     value  in   a  publicly  accessible area  exceeds  the  American  National
     Standards  Institute  (ANSI)  radiation  protection  guide.   The  selection
     of  measurement   locations will  influence  the  distribution  of  power
     densities found  in any  investigation of  environmental RF exposures.   If
     one considers the set of  locations  at  which  we chose to make  spatially
     averaged measurements (Figure  3),  about  5 percent  of the  locations in
     publicly  accessible   areas  have  spatially  averaged  values   exceeding
     200 yW/cm2,  the  value  chosen  as a limit  for continuous  exposure  of
     the  public  by   the   International   Radiation  Protection   Agency,  the
     National Council  on   Radiation  Protection and  Measurement  (in  draft)
     (3),  the  State  of  Massachusetts,   and  Multnomah  County,   Oregon.
     Spatially averaged values at  approximately 11 percent of the  locations
     exceed 100 yW/cm2, a  guideline that the  City of  Portland, Oregon,  has
     proposed for  oublic   exposure  to RF  radiation.   Virtually  all  values
     exceed 1 yW/cm2,  the  actual  upper  range of  the  exposures  most  people
     in the nation experience (4).

5.   Localized unperturbed maximum power  densities exceed the ANSI  radiation
     protection guide in publicly  accessible  areas near the KPLZ tower,  the
     KMGI, KZOK, KMPS tower,  and in the backyard play area near  the Percival
     residence.

6.   Many of the maximum values at ground level inside the Ratelco  North lot
     exceed  1000  yW/cm2;  a  few   exceed  2000  uW/cm2.    These   values
     represent   only  potential   occupational   exposures.     Although   no
     measurements were taken  at  elevated locations on  the towers, there is
     no question that  a worker who ascends  any of the  FM  towers (inside or
     outside the  Ratelco  North lot)  will  encounter fields that exceed  the
     ANSI radiation protection  guide.

7.   All  spatially  averaged  values  near  the residences  we  surveyed  were
     below 100  yW/cm2.  Spatially averaged  values inside  the homes  did  not
     exceed 23 yW/cm2.  The  maximum  unperturbed  value  inside  any  home  was
     305 yW/cm2,  while outside   it 'was  about   350   yW/cm2.    The  maximum

                                 .   11

-------
     perturbed  field  inside  a  home  was  about  350  pW/cm2  near  a  towel
     rack.   The maximum  outdoor  perturbed  field  was  2350  pW/cm2 near  a
     "chinning bar" in the playground near the Percival residence.

8.   Calculated exposure  values  exceed  the actual measured  values by wide
     margins in some cases.  These discrepancies are  :aused  by:   (a) the use
     of a  model  which prudently avoids  underpredicting,  (b) the  terrain  at
     Cougar Mountain  which  presents greater  elevation angles and  distances
     from  any  given  measurement  location  to  an  FM  antenna  than   would  be
     encountered if  the  terrain  were level,  and   (c)  the dense  vegetation
     which acts as  an RF attenuator.

9.   In addition to  potential  health effects,  residents  on Cougar  Mountain
     are   concerned   about   radio   frequency   interference   (RFI).    Their
     electronic equipment, televisions,  recorders,  etc.,  do not  function  as
     expected.   It  should be noted  that FCC Rules and Regulations, Vol.  3
     Part 73, Radio Broadcast Services,  Section  73.318  specifies  limitations
     on FM  radio  "blanketing."Blanketing refers  to a condition caused  by
     high  field  strengths,  which  degrades  FM  radio  reception  because  of
     receiver overload.  The blanketing  field strength  defined by the  FCC  is
     0.562  V/m  which  is  equivalent to  0.0838  pW/cm2.   The data  contained
     in this report (see  Figures 3 and 13)  illustrate that the RF  levels  on
     virtually  the entire  mountaintop  exceed  the  blanketing   value.   We
     experienced what  we  believe  to be  an  RFI problem when  we  were  taking
     data  along  S.E.  173rd  Road  near the  Ratelco North  lot.   Despite the
     fact  that  it  was  surrounded  by a  steel  vehicle  with conductive  film
     covering most of  the window surfaces,  our  computer  ceased to  function
     until we moved further  from the KPLZ tower.   It  is  understandable that
     interference problems would  arise in nearby unshielded  homes.

10.  All  values  presented in  this  report  were the  result  of measurements
     within  about  10  feet  of  the  ground.   It  is  likely  that  the  power
     densities  increase as one moves  to  greater heights,  becoming closer  to
     the antennas,  and  encountering  more of the main beams.  Public  access
     to such elevations  would be  possible  with the  erection  of multistory
     buildings.

11.  Introducing conducting  objects  to   a  relatively  weak  electromagnetic
     field can cause  local power  densities  that are  many  times  as  great  as
     what  would be   measured  in  the  absence  of the  conducting  object.
     Exposure to   such  enhanced  power  densities   is  likely  to  occur for
     significant periods  of  time  only inside a  dwelling  or business.   This
     field  enhancing  effect  that  conducting  objects, which  are   commonly
     found  in  inhabited  structures,  have on  generally weak  fields,  should
     admonish the  FCC and  land  use  planners  as  they rule on  high  power
     antenna, industrial,  and residential siting.'
                                     12

-------
     Table  1.   TRANSMISSION  FREQUENCIES  ON  COUGAR  MOUNTAIN  BY  TOWER  NUMBER

                                           FM Effective
Tower Number     FM Broadcast (MHz)     Radiated Power (kW)     Frequency (MHz)
1




2 KIXI 95.7
KISW 99.9
3 KLSY 92.5
4 Not in use
5 KEZX 98.9
6 KPLZ 101.5
7 KUBE 93.3
8 KQKT 96.5
9 KMGI 107.7
KZOK 102.5
KMPS 94.1




10

11





12






_




(200)
(200)
(200)

(200)
(200)
(200)
(162)
(126)
(200)
(196)




_

*





_






35.700
48.180
173.375
455.025
455.125
43.580
12,410.
43.2

-
-
72.640
-
461.000
461.375
862.6375
863.3875
864.1375
864.8875
865.6375
43.26
151.985
12,470.
12,490.
12,510.
12,530.
12,670.
12,690.
72.
150.920
150.935
159.720
454.050
457.5375
457.5625
                                 (continued)
                                     13

-------
                             Table 1 (continued)

                                          FM Effective
Tower Number     FM Broadcast  (MHz)     Radiated Power (kW)     Frequency (MHz)

     12 (cont.)          -                      -                    457.5075
                                                                     461.050
                                                                     461.100
                                                                     46r.450
                                                                     461.600
                                                                     461.625
                                                                     461.9375
                                                                     462.175
                                                                     462.8625
                                                                     462.9125
                                                                     463.2375
                                                                     463.800
                                                                     464.400
                                                                     464.700
                                                                     464.7625
                                                               861-865  15
                                                               transmiters  on
                                                               a  trucking
                                                               system
                                                                     960.

     13                                        -                    72.
                                                                     44.
                                                                     152.21

     14                 -                      -                    49.520
                                                                     49.580
                                                                     140.050
                                                                     150.920
                                                                     150.950
                                                                     151.595
                                                                     154.040
                                                                     156.500
                                                                     157.590
                                                                     158.700
                                                                     159.660
                                                                     415.050
                                                                     418.950
                                                                     450.6125
                                                                     452.300
                                                                     452.625
                                                                     452.675
                                                                     461.650
                                                                     461.975
                                                                     462.150
                                                                     462.774


                                 (continued)
                                     14

-------
                             Table 1 (Continued)

                                           FM Effective
Tower Number     FM Broadcast (MHz)      Radiated Power (kW)     Frequency  (MHz)

     14 (cont.)          -                      -                    462.925
                                                                     463.225
                                                                     4.63.425
                                                                     463.600
                                                                     463.675
                                                                     464.175
                                                                     862.6125
                                                                     862.6625
                                                                     862.8125
                                                                     862.9375
                                                                     862.9875
                                                                     863.3625
                                                                     863.4125
                                                                     863.5625
                                                                     863.6875
                                                                     863.7375
                                                                     864.1125
                                                                     864.1265
                                                                     864.3125
                                                                     864.4375
                                                                     864.4875
                                                                     864.8625
                                                                     864.9125
                                                                     865.0625
                                                                     865.1875
                                                                     865.2375
                                                                     865.6125
                                                                     865.8125
                                                                     865.9375
                                                                     865.9875

     15          Not in  Use
     16          Not in  Use

     17                                         -                    159.990

     18                  -                      -                    152.090

     19                  -                      -                 1,855.
                                                                  1,915.
                                                                  6,745.
                                                                  6,775.

     20                                         -                 1,885.
                                                                  1,895.


                                 (continued)
                                     15

-------
                              Table 1  (Continued)

                                           FM Effective
Tower Number     FM Broadcast (MHz)     Radiated Power (khl)     Frequency (MHz)

     21                  -                      -                      47.02
                                                                       47.10
                                                                     .147-^08

     22                                         -                      33.160
                                                                       43.
                                                                       72.
                                                                      150.845
                                                                      152.240
                                                                      159.525
                                                                      159.840
                                                                      462.550
                                      16

-------
   Site
                                                       ) MEASUREMENTS AND BROADBAND COMPARISONS
                                                      n Microwatts Per Square Centimeter)
       88-108 MHz (FM)
                           FOISU
Narda   Holaday   FOISD   Holadays
                                  1-2.5 GHz
                           AEL Crossed Log Periodic
        2.5-13 GHz
AEL Crossed Log Periodic
     2-18 GHz
WJ Ominidirectional
   Vehicle Mount
2.  South Gate area
    of Katelco
     North Lot

3.  Near KQKT

4.  Near Ratelco
    South Lot

5.  Near KMGI,
    KZOK, KMPS

6.  Near Percival
    Residence

7.  Near Lennox
    Residence
           81.0    56.7
                                                 0.70
 83.1
760
 8.  Near West Gate of
     Ratelco North Lot

 9.  Inside Ratelco   760
     North

 10.  Near Sparks
      Residence
77.5
12.2
1268
50.5
4.9
80.8
9.0
914
45.6
5.6
1.04
0.74
0.72
0.90
1.14 sak.
           599
370      0.62
          1561     830
         0.53
                                             0.0003 peak, 2 polarizations
                                                                                                .006 peak,
                                                                                                1 polarization
                                                                  (0.000003 for 1.84-1.87 GHz
                                                                  averaged, 2 polarizations)

                                                                  (0.00000007 for 2.178 GHz peak,
                                                                  1 polarization)
                                                         no frequency exceeding noise  level
                                                         on wide band scan

                                                         (0.000007 for 6.775 GHz peak,
                                                         1 polarization)
                                             0.00002  for  1.8S> to  1.92 GHz
                                             peak,  2  polarizations
                                             0.006  for 0.8b  to 0.87 GHz peak,
                                             1 polarization

-------
                       Table 3.   INDOOR  MEASUREMENT  DATA


LENNOX RESIDENCE                            Plane-wave Equivalent Power Density

                                            	         (yW/cm2)	
                                            Spatially Averaged         Maximum

Living Room                                          2                     11
Kitchen                                              2
Bedroom                                            7-9
  Chinning Bar                                       _                    117
  Microscope eyepiece                                -                     35
  Office area                                        2
  Chair                                           5-12
Second Floor Storage                               4-5
  Lamp                                               -                     14
  Over table                                         7
Shower                                               2
Basement                                          2-12
  Near radial arm saw                                -                    129
PERCIVAL RESIDENCE

Living Room                                       5-12
  Near sliding door to deck                          -                      23
Door to Kitchen                                     12
Door frame between kitchen and deck                  -                      70
Kitchen                                           7-23
Near corner of woodstove                             -                      23
Entry Way                                        12-23
Master Bedroom                                      12
  Over bed near ceiling                              -                      59
  Southwest corner                                   -                     305
  Near swag lamp                                     -                     235
Daughter's Bedroom
  Over bed                                          23
  Near bed with electric blanket                     -                      70
  Near south wall                                    -                     282
Bathroom                                          8-12
Deck                                                12                      23
  West end                                          21
  East end                                           4
                                      18

-------
                              Table 3 (continued)
SPARKS RESIDENCE
Living Room
Kitchen
  Window frame
Family Room
  Sliding glass door frame
Master Bedroom
  Metal door frame
  Dressing room
  Shower stall
Bedroom No. 2
  Along curtain rod
Office
  Filing cabinet
  Window
  End of curtain rod
Bathroom
  End of towel bar
  End of shower curtain rod
Entry Way
Utility Room
Garage
  metal bar surface on door
Basement
Bedroom downstairs
  window frame
Furnace room
Bathroom Downstairs
  end of towel rack
Plane-wave Equivalent Power  Density

	(yW/cm2)	

Spatially Averaged

         7
       1-2

       1-2

       1-2

       1-2

       2-7

       2-5
       1-4
       2-5
       1-4
         8

       1-2
       0-1

       1-2
       0-1
Maximum

      15

      26

       7

    7-21

      95

     352

   16-23
      16
     117

      33
     129

       8

   59-70


      20


       8
                                      19

-------
VnSHON
ISLRND
                                                                   LRKE
                                                                 SRMMflMISH
                                                             D
                                                            COUGflR
                                                          MOUNTflIN
                                                               LflKE
                                                              YOUNGS
  Figure 1.  Map of Seattle Area Showing Location of Cougar Mountain.
                                   20

-------
              id
       lOOpW/cm2
                                                    50    100   150   200

                                                        Meters
Figure 2.  Computer  Plot  of  Calculated  Power   Density   Values  for  Cougar
           Mountain.
                                     21

-------
                             FM Broadcast  Band
                                                  Res RH • IHH kH?

                                                  I'olanzat Ions » 3

                                                  Rverage
 ro
 ro
                    f--l- -4—f—-f-4-
                                      	I
B5/B8/85. 10:29 RM 28 Sons
Loot Ion: SITE 2
Processed

flntenni Used: Fiber Optic Isolated Sphencil Dlpole
Frequency Amplitude
(MHz) (dBuV/n)
32. 5 (KLSY) 134.28
93.3 (KUBCI 134.33
94.1 (KHPS) 136.47
95. 7 (KIXI) 125.53
96. 5 (KQKT) 122.91
96.9 (KEZXI 134.94
93.9 (KISH) 136.73
181.5 (KPLZ) 133.53
182.5 (KZOK) 125.38
IB?.? (KHGI) 127.91
Total Band exposure:
Power Density
CuH/cm-J)
6.9?
7.29
II. 76
8. 35
8.52
8.27
12.46
5. 98
B.38
1.64
56.74 uH/cn'2
IB Frequencies Included In the Integration.
OO

QO
G)

CD
                        
-------
            150 -i-
            140 --
                                FM  Broadcast  Band
 ro
 u>
             90
             80
Ret BH - 180 hHi
Poltrlzitlons - 3
Hverige

















US /Rfl yft*i 9*49 PH
DJ^DD'OJ • C ! Tt rrl
Lootlon: SITE 3
Rntenni Uied: Fiber
Frequency
(MHz)
92. 5 (KLSY)
93.3 (KLIBE)
94.1 (KHPS)
95. 7 (KIXI)
9E.S (KQKT)
99.9 (KCZX)
99.9 (KISM)
IBI.S (KPLZ)
102. 5 (KZOK)
IB?. 7 (KHGI)
Totil Bind Exposure


Optic Isolated
flnplltude
(dBuV/r.)
112.86
IM.I7
113.44
113.16
144.88
131.20
109.41
114.37
110.96
IH.0?
:
»»t«rf
1CBD
Spherlcil Dlpole
Power Density
(UH/CB-J)
B.OS
0.B7
0.86
0.BS
80.03
0.3S
0.03
0.07
B.B3
0.87
80.81 uH/cn-2
IB Frequencies Included In the Integntlon.
                     CS)OJ<9-U)GD(S)OJ^'LOCD
                     CDcncnoicDOQQOQ
                                  Frequency (MHz)
Figure 5.   Site 3 FM Spectrum.

-------
              140 -i-
              130 --
                                 FM  Broadcast  Band
                                                        Rat BH - I08 kHz
                                                        Polarizations - 3
                                                        Rverage
           >  110 --
           CQ
           •a
 ro
              80
BS/BB/85. StM PM
Location: SITE 4
flntanna Used: Fiber
Frequency
(MHz)
92.5 (KLSY)
93.3 (KUBE)
94.1 (KMPS)
95.7 (KIXI)
98.5 (KOKT)
98.9 (KEZX)
99.9 (KISM)
' 181. 5 (KPLZ)
IB?. 5 (KZOK)
IB?.? (KHGI)
Total Band Exposure




Optic Isolated Spherical Dlpole
Raplltude
(dBuV/n)
136.2*
127.27
128.31
118.94
117.97
119. 89
123.38
117. 2B
I3B.B9
124.23
:
IB Frequencies Included In the
Poner Density
(uH/cn-2)
1.12
1.41
i.ea
B.2I
B.I7
0.22
8.57
B.M
2.71
8. 78
9.83 uH/cm~2
Integration.
                                   Frequency (MHz)
Figure  6.   Site 4 FM  Spectrum.

-------
             160 -i-
             150 --
                                 FM Broadcast Band
                                                        Ret BH - IBB kHz
                                                        Polarizations - 3
                                                        Average
             130 --
             120 --
 ro
 en
             110 --
             100 --
85/88/65. 6:58 PH
Laotian: SITE 5
Rntenna Used: Tiber
Frequency
(MHz)
92.5 (KLSY)
93.3 (KUBE)
94.1 (KHPS)
95.7 (KIXI)
SE.5 (KOKT)
98.9 (KCZX)
99.9 (KISH)
IBI.5 (KPLZ)
182.5 (KZOK)
187.7 (KHGI)
Total Bind Exposure:
18 Frequencies Inc




Optic Isolated Spherical Dlpole
Rupl Itude
IdBuV/n)
123.48
123.67
HS.I8
125.92
189.46
125.98
124.78
123.19
154.72
141.48

uded In the
Paver Density
(uH/cm'J)
8.59
0.62
87.36
1.84
8.82
1.85
8.78
8. 55
785.69
36.65
914.36 uH/cm-2
Integrat Ion.
                                   Frequency (MHz)
Figure  7.   Site  5 FM Spectrum.

-------
                           FM  Broadcast  Band
                                                 Res BH - 188 kHj
                                                 PoUrlntlonl - 3
                                                 Rvcrage
        80
85/88/85. 7:36 PH SB Scini
Location: SITE 6
Processed

Antenna Used: Fiber Optic Itolatad Spherical Dlpola
Frequency Huplltude
(MHz) (dBuV/.l
92.5 (KlSri 136.34
93.3 (KUBE) 125.7?
94.1 (KMPS) 135.91
95.7 (KIXI) 136.45
96.5 (KQKT) 120.86
96.9 (KEZX) 135.73
99.9 (KISH) 126.94
IBI.5 (KPLZ) 124.43
182.5 (KZOK) 121.76
187.7 (KHGI) I28.8B
Total Band Exposure:
Pover Density

IB. 89
1.88
I.B3
11.72
8.27
9.92
2.BB
B. 74
8.48
8.32
45.57 uH/cn»2
IB Fraquenclei Included In the Integration.
                            Frequency (MHz)
Figure 8.  Site  6 FM Spectrum.

-------
                            FM Broadcast  Band
 IN)
                  ,     ,
Rei BH - 108 kHz
Polarizations - 3
Aver ige





|
II
M
M
II





-^B^^^L
P^^W^™

85/88/85. 8:21 PH
Location: SITE 7
Rntenna Used: Fiber
Frequency
(MHz)
92.5 (KLSY)
93.3 (KUBE)
94.1 (KMPS)
95.7 (KIXI)
96.5 (KQKT)
98.9 (KCZX)
99.9 (KISH)
IBI.5 (KPLZ)
182. 5 (KZOK)
107.7 (KHGI)
Total Bind Exposure
10 Frequencies Inc

IB8 Scans

Optic Isol
ftap 1 1 tude
(dBuV/n)
121.87
HE. 69
IM.45
115.10
131.75
123.97
116.52
115. IB
107.51
112.54
=
luded In th

Processed

ated Spherical Dlpole
Power Density
(uH/cm'2)
8.41
0.12
0.07
0.09
3.97
0.66
0.12
0.09
0.01
0.05
5.59 uH/cm-2
e Integration.
              CD   (S   CM
              GO   CD   C71
                              Frequency (MHz)
Figure 9.  Site 7 FM Spectrum.

-------
                             FM Broadcast  Band
ro
oo
Rei BH - IB0 kHz
Polarizations - 3
Average




1
|








1

'Ww^Ww
05/88/85. 9:43 Prt 58 Scans
Locitlon: SITE 8
Processed

Bntenni Used: Fiber Optic Isolated Spherical Dlpole
Frequency Amplitude
(MHz) (dBuV/m)
93.5 (KLSY) 142.34
93.3 (KUBE) 133.51
94.1 (KHPSI 126.84
95.7 (KIXII 139.81
9E.5 (KQKT) 121.48
98. 9 (KEZX) HB.76
99.9 (KISH) 138.44
IBI.5 (KPLZ) 144.74
182.5 (KZOK) 119.57
187.7 (KHGI) 119.39
Tottl Bind Exposure :
Pover Density
(uH/c«-2)
45.44
4.73
1.87
21.18
8.37
199.34
18.58
79.84
8.24
8.18
378.81 uM/ci>"2
IB Frequencies Included In the Integration.
           80
                                                 S)
                                                     CD

                                                     (9
GO
CD
                              Frequency  (MHz)
Figure 10.   Site 8 FM Spectrum.

-------
             160 -i-
                               FM Broadcast  Band
, 10
R« BH • IBB kHi
Polirlntloni - 3
Rvenge





1








I
rfULl^^
w 'M fi fQC^jRtl
fSPffW
85/86/85. 10:33 PH
Locitlon: SITt 9
Rntenni Used! Fiber
Frequency
(MHz)
93.5 (KLSY)
93.3 (KUBE)
94.1 (KMPS)
95. 7 (KIXI)
96. S (KOKT)
96.9 (KEZX)
99.9 (KISH)
IBI.S (KPLZ)
182.5 (KZOK)
187. 7 (KHGI)
Totil Bind Expoture:
SB Sctni

Optic Iiol
Rnplltude
(dBuV/n)
ISI.67
13-1.09
131.97
149.99
119.26
M6.BE
136.73
139.29
115. BB
121. G2

Processed

ited Spherlcil Dlpole
Power Density
(uH/c.*8)
369.64
6.79
4.18
264.84
8.22
126.84
12. SB
22.52
e.ia
B.39
638.82 uH/cn'2
IB Frequencies Included In the Integration.
              80
                                                    is
                                                        CD
                                                        IS
CO
IS
                                 Frequency (MHz)
 Figure 11.   Site 9 FM Spectrum.

-------
CO
o
                                                                   R« BH • 188 kHz
                                                                   Polirlzitloni •> 3
                                                                   Rviriga
                             —     CM    rvi
                                                                                          85/18/85.  4:44 PH   58 Scini Proc.ited

                                                                                          LOGit Ion:  SITE 7
                                                                                          Rntinni U««d: Tiber Optic Iioltted Spherlcil DIpoU
                                       Frequency (MHz)
 Figure  12.   Site  7  Wideband  Spectrum.

-------
                          Cougar Mountain  Publicly  flccessible  Rreas
             1000
          OJ
          <
          E
          u
          \
          3:
          3
           v>
           c
           0)
          a
           0)
           3
           o
          a.
100
CO
               10
           id
           u

           a.
           x































- WPD
Clt
















• •






P (i
y °
















• i






Iraf
r Po
















•
•••






:), IR
•tland
















MMBBl
»






>A, M
limi




















issachi













-sm
Jr
,-
•
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i than






sett











— m
i^v-
i 	


1% 0






5 St








mm-
m —




f U.






and;








i
•B-







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rH •








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•
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irba






















.
-P
jf
^









n po










pulal







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c
f
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;ion ex














posed





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••••




















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n2


























                    OJ
                        in  —  oj
                                   in
                                       (S)
                                            (3
                                            C\J
                                       C3
                                       in
IS)
ID
(S)
                                                               GO
                                                                    m
             in
             m
GO
en
O)
en
                   Cummu1 ative Percent of Measurement Locations with Spatially

                   Rveraged Pouier Density Values Less than Ordinate Value.
                        in
                                                                     en
                                                                     m
                           co  en
                              en en
                              en en
Figure  13.    Probability  Plot  for   Cougar  Mountain  Spatially  Averaged  Power   Density'  Values   in
              Accessible Areas.

-------
                                                                    1
1 j
1
1 1

540

1

1 i
W ! 704 ' 1
^f i ni
! i
1160* ' |
986 W =-621
	
-"-!
i
.63 = ^^
1

704

.
1
1361

\J Indicates tower 1
supporting FM ' 61°
antennas. 1

9D«
O Indicates tower . 939
which does not i
support an FM | 962
antenna. i
1
610
^ Indicates | -™^
instrument f&
comparison location; |
associated value is . 687
FOISO Value I
Holaday Value j
see Table 2. j 2223
j
All other values were 138S
measured with the 1
Holaday 3001 . ' 469
1
All values have been j
corrected for the 1
instrument's j 61"
frequency response 1
and have been
converted to units of |
microwatts per
squa're centimeter. L 	 	 . 	
469
822
822 704

822 761
610 587
329 587
1
1
1
1
1
1
^/ 234 610 751 822 f22 587 915 704 '
1878 oiu
493 939
1080
1690 2113 "61
,-1690 1972
\£/
1455
1033

822

1

1
1

1
.
1221 |

>2347 """ 1056
4/$S 939
•>2347
1056
563
1244
763
751
> 587 751 1056 610 646 587 822
&







©






0 10 20 30 40 BO 60
Feet

W=.70 \
1

1
1
1
1056 1
i
i
1
1
1




|

1
1
1
1
70 1
1
	 	 j
\
                                                                              area
Figure 14.  RATELCO North Lot Maximum Values.
                                    32

-------
                                  Cougar Mountain -  RRTELCO NORTH Lot
u>
dUUU
2000
1000
^^
OJ
E
u
* 100
^•/
X
M
c
0)
a
l_
Q)
1 10
1


	
























• ANS

























I, f

























lew i






i


















Jersey






.'
•


















stan<





«
••


















Jard-




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•























— mt






















7-
























^
























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p»—
























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•§ —
























^
f~*

























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-• oj in — « oj in Q o s) 03 (S) 03 03 C3 03 in GO cn in •GO a
• • • • •— « oj n ^f in to I^CD cncn cncn«
                       Cummulatlve Percent of Measurement Locations  with Power

                       Density Values Less than Ordinate Value.
cn   cn cn
cn   cn cn
    Figure 15.  Probability Plot of Power Density Values at All Measured Points Inside  RATELCO North Lot.

-------
                                                               RATE LCD
                                                               North Lot
                                                       469
                                                                           = .70
                      200  228 164  218 216

Building
282
282 1
305 '
I

352^7> 305  235  235  282  157 129  94


  235            |


  235            I


                 I

                 i
  282


  792
                Indicates tower supporting FM antenna.
                                                             21 1
            V7 Indicates instrument comparison location;
                 associated value is:  FOISD Value   _T.Kla,   "8
                                   Holaday Value
               All other values were measured with Holaday 3001.

               All values have been corrected for the instrument's
                 frequency response and have been converted to
                 units of microwatts per square centimeter.
               Feet
                        10   20   30   4O
                                          SO  60
                                                   7O
                                                       80
  141
                                                             141
                                                             127
                                                             141
Figure 16.    RATELCO  KUBE Enclosure Maximum Values.
                                                34

-------
                                   150
              N                    352
                                   399


                                   493


                                   587


                                   469
                                  >2347
               469  376  587  399  399 ^N 939 915 986 1033     329  329 200 176 117


                                   821       ^^-.72


                                   469


                                   704


                                   869


                                   704


                                   704
                     Indicates tower supporting FM antennas.


                     Indicates instrument comparison location;


                     associated value is FOISD Value 'see Table 2.
                                     Holaday Value


                     All other values were measured with the
                     Holaday 3001.


                     All values have been corrected for the
                     instrument's frequency response and have
                     been converted to units of microwatts per
                     square centimeter.
                        	Feat	

                        10  20  30  40  SO  60  70  80
Figure  17.   Maximum  Values Near  KMGI/KZOK/KMPS Tower.
                                             35

-------
                                  REFERENCES


1.  An Automated TEM Cell Calibration System, E. D. Mantiply, EPA 520/1-84-024,
    October 1984.

2.  An  Engineering  Assessment  of the  Potential   Impact  of  Federal  Radiation
    Protection Guidance on the AM, FM, and TV Broadcast Services, P. C.~"GaiTey,
    R. A. Tell, EPA 520/6-85-011, April 1985.

3.  Presented at the Annual Meeting of NCRP, Washington, D.C., April 1984.

4.  Population   Exposure   to   VHF   and   UHF  Broadcast   Radiation   in   the
    United States, R. A,  Tell,  E. D.  Mantiply,  Proceedings of  the  IEEE,  Vol.
    68, No. 1, January 1980.
                                     36

-------
                                   GLOSSARY


    Gigahertz (GHz); 1 GHz equals 1,000,000,000 Hz.

    Hertz  (Hz)  is  a. unit for  expressing frequency  equivalent to  cycles per
second, i.e., one Hertz is defined as one cycle per second.

    Kilohertz (kHz); 1 kHz equals 1000 Hz.

    Maximum Value refers'  to  the highest power density value  that  can be found
in a given area based  on  electric  field measurements, normally associated with
areas of limited extent wherein only partial body exposures might occur.

    Maximum Value  in  a Perturbed  Field  refers  to the  maximum power density
value which we believe is caused by the  convergence of  electric field lines at
a  conducting  object.   While  these  elevated  levels  are   artifacts  of  the
conducting objects  in  the field and are  highly  localized in  volume,  they are
real, measurable fields.

    Maximum Value  in  Unperturbed  Field refers to  that maximum power density
value which  exists  in the absence  of any conducting  object  in the immediate
vicinity  (i.e.  a few  feet).   These  are  the maximum  values  found  in  "free
space."

    Megahertz (MHz); 1 MHz equals 1,000,000 Hz.

                                           2
     Microwatt per Square  Centimeter (uW/cm ); an  expression for the power
density of an electromagnetic field, 1000 jiW/cm2  = 1 mW/cm2.
                                            2
     Milliwatts per Square Centimeter (mW/cm );  an expression for the power
density of an electromagnetic field, 1 mW/cm2 = 1000 yW/cm2.

     Power  Density  is   a   term  to  describe  the   intensity  of  incident
electromagnetic radiation  fields.

     Spatially Averaged  Value  refers  to our  best estimate  of the average
power density or typicalpower density  that exists  in  a  given  location.
(i.e.  the  average  value   that  exists  over  a  vertical   area   of  about
70 square feet.)

     Rate!co  refers  to Ratelco  Incorporated,  a  company  which owns  several
towers atop Cougar Mountain  and  leases  tower  space to broadcasters,  point to
point users, land mobile users, etc.

     Volts per Meter (V/m) is  an expression  for  the strength  of an  electric
field.
                                     37

-------
                                   APPENDIX
                     EQUIPMENT AND CALIBRATION INFORMATION

    The  equipment  used  during  the  Cougar   Mountain  study  is  listed  below.
Calibration data are detailed for each instrument in the following pages.
Broadband Equipment
    Holaday Industries   Model 3001, S/N 26026  Meter
                                     S/N 056    Electric Field Probe

    Narda                Model 8616, S/N 05016  Meter
                         Model 8631, S/N 03026  Magnetic Field Probe

Narrowband Equipment

    NanoFast Fiber Optic Isolated Spherical Dipole Model EFS-2, S/N 2927

    Ailtech Singer Dipole Antenna Set Model DM-105A-T3, S/N 95414-13

    American Electronic Laboratories (AEL)  Crossed Log Periodic Antenna
    Model APX 1293, S/N 108

    Watkins Johnson Omnidirectional  Antenna  Model 8549, S/N 17

    Hewlett Packard 8566A Spectrum Analyzer,  S/N 1918A00731 (display)
                                             S/N 1918A00220 (analyzer)

    Hewlett Packard 9845B Desktop Computer,  S/N 1838A02156
                                     38

-------
  u>
                  Holaday  HI--3001  s/n  26026,  E  Probe  s/n  056
           o
           i.
           1_
          u

          m
          -a
               0
                                     0.75       0.75 o 74 0.75  0.75  u-^.b  0.75
                                      T   0.73   T  "'-t-    T    T
                     0.70
                          0.65  0.65
                     0. 12
11
     0     11
                     (i     (
-L   0.12  0.12  0'13 0.12 0.12  0'13
                                                                    0. 17   -L
                                                                         0. 15
                           0.0B
                       88    90   92   94   96   98   100  102   104   106   108


                                        Frequency  (MHz)
Figure Al.  Holaday Model 3001 Electric Field Calibration in FM Frequency  Band.

-------
           L.
           O
           L.
           L.
           LJ

           m
           TJ
                 Narda  8616  s/n  05016,   H  Probe  8631  s/n  03026
                I       _ _    	          __    	       	         	,	
0
              -1
                      0.32  0.33  0.33  0.32 0<30 0.31
                                                     ..37
             (I    (I    0
                     -0.23      -0.23
                                                                    0.3S
                                            (I
(i
                                            '   -0.27
                                                    -0.16   J_   -L    _L    _
                                                         -0.21 -0.20 -0.21 -0.22
                            -I —
                       88   90   92   94    96    98    100   102   104   106  108

                                         Frequency  (MHz)
Figure A2.  Narda Model 8616 (8631 Probe)  Magnetic Field Calibration in  FM Frequency Band.

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             55
       PQ
       O
       (0
       c
       c
       OJ
      .*•>
      . c
      CE
50
             45
               .01
          50
100
150
200
250
300
350
400
450
500
                                            Frequency  (MHz)


Figure A3.  NanoFast Model EFS-2  Fiber Optic Isolated Spherical Dipole Antenna Factor.

-------
  ro
                    40 n
                    30-
                m
                T3
2.  20-
                o
                CO
UL   10-
                co
                C
                C
                
-------
 CO
          PQ
          a
          id
          
-------
                                               Frequency  (GHz)
Figure A6.  Watkins Johnson Model WJ 8549 Antenna Factor for 1-18 GHz.

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