group (unit 8) has a synchro test point panel to monitor input  synchro  voltages. The  OCC  installed  in  the  equipment  room  (unit  15) is   a   system/bootstrap   bus   monitor   (SBBM)   that performs  on-line  system  testing  and  troubleshooting, and computer bootstrap program loading. The memory loader/verifier  (MLV)  (unit  13),  stored  in  the  equipment room, is used for the following purposes: Load  and  verify  operational  programs  from cassettes Initiate  AN/AYK-14  self-test  and  display  results Load   diagnostics   and   provide   maintenance interface  and  control Write cassette memory with received data Display   and   change   register   and   memory locations The SPN radar test set (RTS) (unit 22) is used to align, calibrate, and maintain the radar/SMS subsystem. The  retractable  alignment  mast  (unit  23)  elevates  the SPN  RTS  and  a  collocated  corner  reflector  to  a minimum of 19 feet above the carrier flight deck for system calibration. The UPM radar test set (unit 26) is also used to test and calibrate the radar/SMS subsystem. This  test  set  combines  the  functions  of  a  spectrum analyzer and synchroscope to provide pulse or CW test signals and visual spectrum indication. It also has a direct reading cavity frequency meter, and a power level meter. Maintenance Organizational maintenance is performed by ET personnel (NEC ET-1524). It consists of removal and replacement  of  plug-in  assemblies  and  chassis-mounted parts. You   can   isolate   faults   using   the built-in-test  (BIT),  built-in-test  equipment  (BITE), general-purpose  electronics  test  equipment  (GPETE), special-purpose  test  equipment  (SPETE),  and maintenance assist modules (MAM). Depot  level  maintenance  includes  repair  of  failed printed circuit boards (PCBs) or modules and major repairs,   such   as   overhaul,   refurbishment,   and calibration. AN/FPN-63  PAR The  AN/FPN-63(V)  Precision  Approach  Radar (PAR) is used at naval air stations (NAS) and Marine Corps  air  stations  (MCAS)  for  air  traffic  control operations. It  replaces  the  PAR  portion  of  the AN/CPN-4  family  of  equipment.  The  AN/MPN-23  is  a version of the same equipment mounted on a trailer. General  Theory  of  Operation Although the AN/FPN-63(V) is functionally and operationally   similar   to   the   PAR   portion   of   the AN/CPN-4,  it  uses  a  modified  version  of  the AN/CPN-4A   PAR   antenna   system.   The   antenna modifications reduce signal side lobes and minimize ground and precipitation clutter. The AN/FPN-63(V) is based on solid-state circuitry and includes a digital moving target indicator (mti). The modification also includes  a  remote  control  subsystem  that  provides complete operational use of the PAR up to 10,000 feet from the radar van. The  solid-state  AZ-EL  range  indicator  generates  its own internal map, sweeps, range marks, and cursors. A single  curser  adjustment  allows  alignment  of  each curser with the runway centerline. Independent transmitters and receivers provide one operational channel and one “hot standby” channel. This  allows  the  operator  to  use  one  set  of  equipment, while a technician performs maintenance on the other set.  Thus,  service  is  never  interrupted. Configuration A remote control turntable unit and the associated remote  control  panels  allow  positioning  of  the  radar  for multiple runway operation. Stations not requiring multiple   runway   operation   use   a   fixed-mounted AN/FPN-63. All radar components are in racks and enclosures of the radar sets, with empty spaces covered by blank front panels. The number of indicators varies by site. Maintenance Organizational maintenance is performed by ET personnel (NEC ET-1579) and includes performance verification, testing, alignment, and fault isolation. Repair of equipment consists of the replacement of discrete  chassis  components  and  piece  parts. The  prime  contractor  performs  all  depot-level maintenance. If you have any modules or PCBs that your  organization  cannot  repair,  return  them  to  the  depot facility. 2-18