Engineering Definitions
"A" "B" "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M",
"N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z"

'Ha' to 'Hd', 'He', 'Hf' to 'Hor', 'Hor' to 'Hz',

Board Mount Shrouded Header

Shrouded Header. [Box Header] A male connector having exposed pins surrounded by side walls which are molded onto a plastic base. Shrouded Headers are produced in either single row or double rows having a minimum of two pins. A 1-pin header would just a test-point. Common Headers are 0.1 inch spacing, pin-to-pin. Female connectors having the same pin spacing are used as an interface. Headers are common in PC motherboards, and are very common as Jumper blocks.
Additional names used to describe a header include; Pin strip header, pin header, ribbon cable headers, box header, or pin receptacle.

Headers height may be high Profile or low profile.
Headers protection may be an Un-Shrouded Header or may be a
Shrouded Header, with side walls [shown below].
Headers Pin separation may have 0.1 inch separation [shown below] or 2mm separation.
Pitch [all styles] .200" (5.08mm), .156" (3.96mm), .100" (2.54mm), .079" (2mm), .050" x .100" (1.27 x 2.54mm),
.050" x .050" (1.27 x 1.27mm), .0394" (1mm), .0315" (.8mm), .0197" (.5mm) pin pitch.
Also see Header Manufacturers

Dual Row Through-hole Vertical Header

Dual Row Header is the most common styles. The Dual Row Header may be used as a male terminal for a connector or a Jumper block. Although Shrouded Headers are never used as a jumper block.

10-pin Board Mount Shrouded Header
Shrouded Header

Personal Computers use Vertical Shrouded Headers as peripheral device connections, as in CD drives and Disk drives. The three Shrouded Headers shown below are Mother-board connectors for two Hard Disk Drives [blue] and a Floppy disk drive [black]. While Un-Shrouded Headers are used for jumpers, power or fan connections. Some headers are color coded to donate functions.

PC Board Mount Shrouded Headers
Shrouded Headers

The board side header is always a male connector, as shown in the attached pictures. While the cable side is always a female connector as shown in the graphic to the right. The cable side may be a discrete wire cable attachment or an IDC Header which accepts a ribbon cable.

Note that the cable end [female-header] of this particular mate is not keyed, as shown with the cut-outs on the male headers depicted.

Dual Row Through-hole Right Angle Header

Right angle headers may be dual row or single row components.
A Through-hole header is shown below, but surface mount headers are possible.

Dual Row Right Angle Shrouded Header
Keyed Right Angle Header

Additional possible header features;
Suppression plates [Ferrite slabs] help reduce EMI/RFI interference [located between the PCB and header].

Insulator standoffs to rise the body of the header just above the PCB surface [for easier cleaning].

Locking bars to clamp the cable to the connector [graphic right].

Most headers will also have a mark to indicate pin 1, as seen with the arrow on the header above.

Reduction of hazardous metals RoHS

Straight Locking Shrouded Header
Straight locking Header

MIL-DTL-83503C; covers the cable or board side.
Electrical Flat Cable or Printed Wiring Board Connectors
The connector will be marked with M83503/25
M83503 is the specification number, the /25 is the specific slash sheet defining a particular type of connector.

MIL-DTL-83503 General Specification for Nonenvironmental Flat Cable, and/or Printed Wiring Board Electrical Connectors
MIL-DTL-83503/6 Dual-in-Line Plug connector for Terminating Flat Cable Round Conductors on .050 Centers for Mating with Standard Dip Sockets, .100 x .300 Contact Spacing, .100 x .400 Contact Spacing, and .100 x .600 Contact Spacing
MIL-DTL-83503/7 Connector Plug with Dual Polarization, Rounded, Insulation Displacement, Non-Removable Socket Contacts (.100 x .100 Spacing), Flat Cable
MIL-DTL-83503/20 Flat Cable Header, Right Angle (.100 Spacing) with Polarizing Feature Solderless Wrap-post or PWB Termination
MIL-DTL-83503/21 Flat Cable Header, Straight Thru (.100 Spacing) with Polarizing Feature Solderless Wrap-post or PWB Termination
MIL-DTL-83503/22 Flat Cable Connector Socket Insulation Displacement
MIL-DTL-83503/23 Flat Cable Connector, Printed Wiring Board Solder Transition for Terminating Round Conductors on .050 Inch Centers
MIL-DTL-83503/24 Flat Cable Four Wall Header, Right Angle (.100 Spacing) with Polarizing Feature Solderless Wrap-post or PWB Termination
MIL-DTL-83503/25 Flat Cable Four Wall Header, Straight Thru (.100 Spacing) with Polarizing Feature, Solderless Wrap Post or PWB Termination

PC motherboard

Distributor rolodex Electronic Components Electronic Equipment EDA CDROM Software Engineering Standards, BOB card Cabled Computer Bus Electronic Engineering Design Table Conversion DB9-to-DB25.
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