Information Technology Reference
In-Depth Information
The color codes for horizontal 150-ohm STP-A cable are:
Pair
Colors
Pair 1
Red, Green
Pair 2
Orange, Black
This color code corresponds to the markings for the IDC contacts within the Data
Connector and makes the cable conductors very easy to match with their proper contact.
The Data Connector outlet is a version of the standard Data Connector that is
mounted in a cover plate. The cover plate is attached to a standard outlet box. The
STP-A station cable is terminated directly in the outlet connector. Versions of Data
Connector faceplates are available that contain both the Data Connector and one
or more standard modular jacks.
The Data Connector and STP-A cabling system is a robust system that offers
certification to 300 MHz, three times the current maximum frequency specification
of standard UTP systems.
Coax Jacks
Coax jacks are another type of outlet jack. The BNC coax jack is commonly
encountered in 10Base2 Ethernet cabling systems. This cabling system calls for the
thinnet segment cable to be run from one workstation position to the next, and so
on, until you reach the end of the segment. At each workstation location, the two
cable sections are joined together by a BNC-T, and the center position of the T is
connected to the workstation network adapter. The workstation essentially taps the
coax line to become a part of the network. The method generally does not allow an
extra stub of coax from the tap to the workstation; both cable sections must be
extended all the way to the T at the workstation adapter.
Each fixed 10Base2 coax outlet, thus, needs two coax connectors, one for each
cable section leading to the workstation. The customary outlet has two separate
female BNC connectors on the faceplate, each connected to one of the two cable sec-
tions at the rear of the faceplate. There are two methods to connect the cable sec-
tions to the rear of the faceplate.
One method connects bulkhead-mounted female connectors directly to each
cable end. Each connector is inserted through a d-keyed hole in the plate and
secured with a thin washer and nut. The alternative method places two bulkhead-
mount barrel connector/adapters in the holes of the plate. The coax cable ends in
the wall are terminated with male BNC connectors, which are then connected to the
back side of the bulkhead adapters. From the front, the plates look the same, regard-
less of the method you use to connect the cable ends.
