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 PUBLIC  NOTICE  Federal  Communications  Commission  445  12th  St.,  S.  W.  Washington,  D.  C.  20554  News  Media  Information  202  /  418-  0500  Internet:  http://  www.  fcc.  gov  TTY:  1-  888-  835-  5322 
 DA  05-  2741  October  25,  2005 
 MEDIA  BUREAU  ADOPTS  SIMPLIFIED  APPLICATION  PROCEDURES  FOR  AM  NONDIRECTIONAL  KINSTAR  ANTENNAS 
 By  this  Public  Notice,  the  Media  Bureau  (“  Bureau”)  announces  simplified  procedures  for  AM  station  construction  permit  applications  which  specify  nondirectional  KinStar  antennas.  Based  on  its  review  of 
 the  KinStar  field  tests  and  submitted  reports,  the  Bureau  announces  that  it  will  not  routinely  require  the  submission  of  a  proof  of  performance,  current  distribution  measurements,  or  a  formula  for  the  vertical 
 plane  radiation  characteristic  for  nondirectional  AM  facilities  which  utilize  these  antennas. 
 The  KinStar  antenna,  developed  by  Star-  H  Corporation  and  manufactured  by  Kintronic  Laboratories,  Inc.,  is  approximately  one-  third  the  height  of  the  standard  quarter-  wave  antenna  used  by  many  AM  stations. 
 The  low-  profile  KinStar  antenna  affords  AM  licensees  the  flexibility  to  place  antennas  in  areas  where  taller  towers  may  be  unacceptable.  In  most  circumstances,  the  KinStar  antenna  also  may  be  more 
 economical  to  build  and  maintain  than  a  standard  antenna.  Applicants  may  only  specify  the  KinStar  antenna  for  nondirectional  use.  The  Bureau  will  consider  authorizing  the  use  of  directional  KinStar  arrays 
 when  more  information  is  available. 
 The  KinStar  antenna  consists  of  a  cage  of  vertical  wires  (usually  four),  symmetrically  arranged  around  a  central  support.  The  vertical  wires  extend  to  a  height  of  approximately  0.08  wavelength  (75  feet  at  a 
 frequency  of  1000  kHz).  Each  vertical  wire  is  connected  to  a  horizontal  top-  loading  wire  extending  to  a  radial  distance  of  approximately  0.17  wavelength  (169  feet  at  1000  kHz).  The  KinStar  antenna  requires 
 use  of  the  standard  120-  radial,  one-  quarter  wave,  buried  ground  system.  Attachment  A  to  this  Public  Notice  is  a  report  providing  details  of  the  construction,  modeling,  and  field  testing  of  the  KinStar  antenna. 


 Both  field  tests  and  computer  modeling  using  the  Numerical  Electromagnetic  Code  (NEC)  4.1  method  of  moments  program  indicate  that  the  KinStar  antenna  produces  an  essentially  omnidirectional  radiation 
 pattern  in  the  horizontal  plane.  The  developers’  tests  also  show  that  the  KinStar  antenna  meets  the  minimum  efficiency  for  Class  B,  C,  and  D  stations.  1  The  elevation  pattern  of  the  KinStar  antenna  can  be 
 represented  by  the  formula  in  Section  73.160(  b)(  2)  of  the  Commission’s  rules  for  a  top-  loaded  tower,  using  an  effective  value  of  top-  loading  determined  by  moment  method  modeling.  AM  applicants  shall 
 use  the  manufacturer’s  computed  figures  for  the  efficiency  of  the  antenna  and  for  the  effective  top-  loading.  2 


 1  See  47  C.  F.  R.  §  73.  189(  b)(  2)(  ii). 
 2  See  47  C.  F.  R.  §  73.  160(  b)(  2).  The  effective  top-  loading,  represented  by  the  variable  B  in  the  formula,  is  the 
 difference  in  electrical  degrees  between  the  apparent  height  and  the  physical  height  of  the  antenna. 
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