﻿Directive 
  System 
  of 
  Wireless 
  Telegraphy. 
  655 
  

  

  the 
  receiving 
  radiogoniometer 
  was 
  turned 
  in 
  the 
  opposite 
  

   direction, 
  which 
  was 
  precisely 
  the 
  object 
  to 
  be 
  achieved. 
  

  

  Fig. 
  16. 
  

  

  06 
  

  

  152 
  

  

  The 
  directive 
  system 
  of 
  wireless 
  telegraphy 
  described 
  can 
  

   be 
  employed 
  in 
  many 
  ways, 
  according 
  to 
  the 
  requirements, 
  

   owing 
  to 
  the 
  facility 
  with 
  which 
  one 
  can 
  pass 
  from 
  one 
  

   system 
  to 
  the 
  other. 
  For 
  example, 
  when 
  the 
  operator 
  expects 
  

   a 
  message 
  from 
  a 
  station 
  whose 
  position 
  is 
  unknown, 
  he 
  

   could 
  employ 
  the 
  single 
  vertical 
  antenna 
  system 
  ; 
  a 
  soon 
  as 
  

   reception 
  is 
  effected 
  he 
  can, 
  by 
  using 
  either 
  the 
  bilateral 
  or 
  

   unilateral 
  system, 
  determine 
  the 
  direction 
  and 
  upon 
  which 
  

   side 
  the 
  transmitting 
  station 
  lies, 
  and 
  make 
  himself 
  independ- 
  

   ent 
  of 
  other 
  transmissions. 
  

  

  For 
  the 
  transmission 
  the 
  operator 
  could, 
  similarly, 
  employ 
  

   the 
  system 
  with 
  circular 
  radiation 
  when 
  he 
  does 
  not 
  know 
  

   the 
  position 
  of 
  the 
  receiving 
  station 
  or 
  when 
  he 
  wishes 
  to 
  

   send 
  the 
  same 
  message 
  to 
  several 
  stations. 
  He 
  could 
  in 
  other 
  

   cases 
  use 
  the 
  unilateral 
  or 
  bilateral 
  system 
  according 
  to 
  the 
  

   position 
  of 
  the 
  stations 
  which 
  should 
  not 
  receive 
  the 
  messages. 
  

  

  