Teledyne HPAC-2005, Руководство по эксплуатации

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3 RU SSPA Chassis Operations Manual 205356 REV T 145
This section briefly describes the basic theory related to the physical layer of
10/100Bas-T networking, as well as proper wiring techniques.
There are several classifications of cable used for twisted-pair networks. Recommend-
ed cable for all new installations is Category 5 (or CAT 5). CAT 5 cable has four twist-
ed pairs of wire for a total of eight individually insulated wires. Each pair is color coded
with one wire having a solid color (blue, orange, green, or brown) twisted around a
second wire with a white background and a stripe of the same color. The solid colors
may have a white stripe in some cables. Cable colors are commonly described using
the background color followed by the color of the stripe; e.g., white-orange is a cable
with a white background and an orange stripe.
The straight through and crossover patch cables are terminated with CAT 5 RJ-45
modular plugs. RJ-45 plugs are similar to those you’ll see on the end of your tele-
phone cable except they have eight versus four or six contacts on the end of the plug
and they are about twice as big. Make sure they are rated for CAT 5 wiring. (RJ
means “Registered Jack”). A special Modular Plug Crimping Tool (such as that shown
in
Figure B-1
) is needed for proper wiring.
The 10BASE-T and 100BASE-TX Ethernets consist of two transmission lines. Each
transmission line is a pair of twisted wires. One pair receives data signals and the oth-
er pair transmits data signals. A balanced line driver or transmitter is at one end of one
of these lines and a line receiver is at the other end. A simplified schematic for one of
these lines and its transmitter and receiver is shown in
Figure B-2
.
Figure B-1: Modular Plug Crimping Tool
Figure B-2: Transmission Line
Appendix B: Proper 10/100 Base-T
Ethernet Cable Wiring