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FCC68 / RJxx Series Connectors
Description | Applications | Pin Assignments | Assembly Instructions

Description
Flat plastic connector (normally clear plastic plug) with latch on one side. Available in 4, 6 and 8-way shells, the 6-way type is also available with only 4 pins fitted. The plug latches into the socket and the tab on the side of the plug is squeezed to release it. Used on computer networks and telephones. Similar in appearance to BT telephone plugs (UK).
Typical Applications
4-way shell, 4-pin - Telephone handsets (UK)
6-way shell, 4-pin (RJ11) - Telephone line connections (USA), Modems
8-way shell, 8-pin (RJ45) - 10Base-T and 100Base-TX Computer Networks
Pin Assignments
10Base-T / 100Base-TX Network Connections (Computer End):

| Pin | Function | Cable Colour |
|---|---|---|
| 1 | Transmit Data + | White / Orange Stripe |
| 2 | Transmit Data - | Orange |
| 3 | Receive Data + | White / Green Stripe |
| 4 | Unused | Blue |
| 5 | Unused | White / Blue Stripe |
| 6 | Receive Data - | Green |
| 7 | Unused | White / Brown Stripe |
| 8 | Unused | Brown |
More pin-outs coming soon.
Connector Assembly Instructions
Plugs:
Normally have IDC terminals. To assemble these, the sheath is stripped from the cable and the cores inserted into the channels in the plug. A crimping tool or die is then needed to push the pins flush, piercing the insulation and making contact with the conductors. The tool will also push the cable clamp down onto the sheath.
Sockets:
PCB mounting sockets are soldered to the PCB, extra pins may be provided to secure the component. Wall mounting sockets have IDC terminals. An insertion tool is needed to push the cable cores into the terminals. Doing so will pierce the insulation and make the connection.