Internal Connectors

for internal and external connectors (fig. 2-21). Circular connectors can have over 100 pins or contacts. The contacts or pins located on either the receptacle or plug are usually round and can be male or female. Circular connectors can be secured to protect against shock and vibration with either complete or partially threaded shells (breech lock) or bayonet-style (pin and curved slot); neither kind requires internal or external screws for securing the mating parts. Externally, provisions can be made for shielding these connectors from EMI and RFI. Terminations of conductor to receptacle include solder (2M or basic) and solderless (wire wrap, crimping, pin removal and insertion, MTIDC or IDC, or AMP TERMI-POINT). Terminations of conductor to plug include solder (2M and basic) and solderless (crimping and pin removal and insertion). Combinations of termination are often used. Fiber optic connectors fall into the circular connector category. Refer to NEETS, Module 24, Introduction to Fiber Optics, for a discussion of the mating of fiberoptic connectors. COAXIAL CONNECTORS.— Coaxial con- nectors are designed for single, twin (twinax), and triple (triaxial) conductors (fig. 2-22). Refer to MIL-C-17 for connector specifications. Contacts or pins located on either the receptacle or plug are round and can be male or female. Coaxial connectors are secured bayonet-style (pin and curved slot) to protect against shock and vibration and for quick removal and replacement. Figure 2-21.—Circu1ar multipin connector. Figure 2-22.—Coaxial connector. Externally, provisions can be made for shielding these connectors from EMI and RFI. Terminations of conductor to receptacle include solder (2M or basic) and solderless (wire wrap, crimping, and pin removal and insertion). Terminations of conductor to plug include solder (2M and basic) and solderless (crimping, and pin removal and insertion). Combinations of termination are often used. COMPONENT CONNECTORS.— Although we may not think of it as a connector, a wire attached to a component’s lead also forms a connection. The most commonly used methods of securing a wire to a component’s lead are soldering and wire wrapping. For example, pushbutton indicators use wire wrap connections to secure a conductor(s) to its pin(s). Wire wrapping is often preferred because it is quick to remove and install, and it is strong. Also, you do not have to apply heat to the conductor. This prevents damage to the conductor’s insulation that can be caused by using a soldering iron. Internal Connectors Rather than have wires running everywhere inside the computer frame or cabinet and between the units, various methods are used to connect the conductors from point to point and to organize the conductors. Connectors are used inside the computer to interconnect the major individual units of the computer. Individual conductors are used to route each signal between the connectors of the major units and to 2-18