Maintenance   Indicators   or   Diagnostic Light-Emitting  Diodes  (LEDs).—  Maintenance indicators  or  LEDs  provide  you  a  readily  visible indication to tell you when the equipment is operating normally and when it is operating abnormally. Refer to your computer’s technical manual or owner’s manual for their locations and operation. Test Points.— Test points are usually located on the outer edge of pcb’s. They can provide you with status or  operational  information  with  voltage  levels  and/or waveforms. Refer to the computer’s technical manuals for  details. COMPUTER CONNECTORS AND CABLES Computers  must  have  an  organized  way  to exchange and route data and power signals internally and  externally.  Computers  must  have  a  place  where  the signals leave the computer externally and talk to other computers  and/or  other  equipments,  peripherals, displays systems, and/or communication systems. The computer’s  technical  manual  or  owner’s  manual provides parts replacement information, recommended tools and test equipment, internal and external signal distribution,   and   I/O   interface. The  following documents also provide information useful in the maintenance  of  computer  connections  and  cabling. They  define  the  standards  and  specifications  of  the interface(s) that the computer uses as well as the standards and specifications of the actual repairs to the internal and external connectors and cables. l MIL-STD-2000,  Standard Requirements for Electrical  and  Electronic  Assemblies—  Provides associated  standards  and  specifications  that  can  be  used when  making  solder  repairs  to  connectors  and  their conductors. MIL-STD-2000 provides the standards for the actual solder terminations. l MIL-STD-2036,  General  Requirements  for Electronic  Equipment  Specifications—  Provides a list of the standard external interfaces; parallel and serial interface formats and metallic and fiber optic cabling. The interfaces listed in MIL-STD-2036 define the requirements  of  each  standard:  mechanical,  elec- trical,   functional,   procedural,   and   any   other requirements that do not fall into any of the four listed categories. l NEETS,  Module  4,  Introduction  to  Electrical Conductors,  Wiring  Techniques,  and  Schematic Reading— Provides information on conductor and cable   (includes   coaxial)   architecture   and characteristics,  wiring  and  repair  techniques,  and  signal interpretation and distribution. * NEETS,   Module   19,   The   Technician’s Handbook—  Provides  connector  and  cable  information; references,  types  and  construction/description,  gen- eral   application   data,   identification,   and   insert arrangement. l NEETS,  Module  24,  Introduction  to  Fiber Optics— Provides fiber optic theory and operation and connector and cable information. l EIMB,  Installation   Standards,   NAVSEA 0967-LP-000-0110—   Provides connector and cable information;   references,   identification   for interpretation  and  distribution,  and  installation  and repair (includes MIL-STDs of specialized tools). . Naval  Shore  Electronics  Criteria,  Installation Standards  and  Practices,  0280-LP-900-8000  — Provides connector and cable information; references, identification for interpretation and distribution, and installation   and   repair   (includes   MIL-STDs   of specialized  tools). l Miniature/Microminiature   (2M)   Electronic Repair   Program,  NAVSEA  TE000-AAA-HBR 010/2M, Vol. 1; 020, Vol. 2; 030, Vol. 3 —Provide the same   type   of   information   as   MIL-STD-2000 concerning solder repairs to a connectors and their conductors. Remember, when making repairs to the connectors and cables, use identical replacement parts or suitable substitutions. This is very important. Let’s start with the  computer’s  internal  connectors,  then  external connectors, and finally the cables. Connector Architectures In  electronics,  connectors  are  designed  to  terminate pcb’s,  conductors,  and  cables  between  electronic circuits  within  a  system,  between  systems  and subsystems  and  their  power  sources.  Connectors interconnect  circuits  on  circuit  boards  with backplanes/backpanels,  motherboards,  or  wiring  within a frame or cabinet of a computer (set). Connectors also terminate  the  cables  interconnecting  the  external equipment and the computer. They come in many shapes   and   sizes. The   interfaces   listed   in MIL-STD-2036  dictate  the  requirements  needed  for connectors. A connector consists of a connector 2-15