Acquisitioning   System   for   the   SEASPARROW missile system. Control Group The Control Group provides computer control for an   equipment   group,   processes   target   detections   to develop and maintain a track file, and interfaces with the specific weapon system being used.   The Control Group normally consists of the following equipment: a computer,  data  terminal  set,  magnetic  tape  unit,  and test set. Support Systems The equipment we discussed above composes the core  of  the  radar  system. To  operate  properly  and efficiently,   it   requires   a   certain   amount   of   support equipment. Examples   of   such   equipment   include power supplies (some also have frequency converters), chilled water systems, and dry air systems.   Although your radar system normally receives 440 VAC directly from  the  ship’s  primary  power  source,  it  has  other voltage requirements that may be stepped up, stepped down,  or  converted  in  order  to  make  the  radar  fully operational.    High-voltage  amplifiers  and  peripheral equipment associated with producing RF energy create tremendous  amounts  of  heat.    Chilled  water  systems remove excessive heat from such equipment.  Cooling systems may be either liquid-to-liquid or liquid-to-air types   that   use   either   sea   water,   or   chilled   water provided by the ship itself.   Another important support system is the dry air system. Dry air is used for keeping the internal part of the waveguide assembly moisture free and to aid in properly conducting the RF energy being transmitted.   The dry air may be either air taken from ship spaces and circulated through various filters or dehydrated air provided by the ship.  Some systems use a special gas for their waveguides.  An example of this is the Mk 92 Fire Control System, which uses the gas SF6 for its Continuous Wave Illumination (CWI) mode. These are very important support systems to your radar.   As you know, any system is only as good as its weakest link.  Therefore, you must be sure to maintain the support equipment as required by the equipment’s technical manuals and maintenance instructions. Stable Elements Hitting a target on a regular basis requires that the gun  or  launcher  be  stable  in  relation  to  the  target. Ideally, the platform on which the gun or launcher is mounted is stable throughout the target acquisition and destruction cycle. Unfortunately Navy ships, on which the guns and launchers are mounted, are seldom stable. In  even  the  calmest  sea,  they  pitch  and  roll  to  some extent.    The  solution  lies  in  stabilizing  the  guns  and launchers  while  the  ship  continues  to  pitch  and  roll. This is done with gyroscopes (gyros) installed in the fire control systems. Gyros   provide   a   stable   platform,   called   the horizontal   plane,   as   an   unvarying   reference   from which the fire control problem is computed.  The basic fundamentals  and  functions  of  gyros  are  covered  in NEETS  Module  15—Principles  of  Synchros,  Servos, and Gyros. In fire control, we call the stabilizing unit a  stable element.  As its name implies, the stable element uses a stabilizing   gyro. The   stabilizing   gyro   is   also   the primary reference for navigation of the ship.   It gives the  ship  a  true  North  reference  for  all  navigational equipment.  The  WSN-2  or  WSN-5  are  examples  of 1-11 3A1A1 SEARCH   RADAR RADOME  ASSEMBLY 3A1A2 SEARCH RADAR ANTENNA ASSEMBLY 3A1A7 TRACK ANTENNA FORWARD 3A1A13 TRACK RADAR RADOME CABLING DETAILS OMITTED FOR   CLARITY NOTE: LEFT   SIDE   CUTAWAY   VIEW FCRf0112 Figure 1-12.—Example of a search and track radome.