DARKSTAR TECHNOLOGIES D220, Руководство по эксплуатации

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Features
The D220 is a simple, low-cost approach to testing coaxial cables for thin Ethernet
(10BASE-2). It’s easy to use and can fit easily in your pocket or tool kit. The
D220 performs five different tests on your coax and displays the status using
leds. The two-piece design allows users to test cables either before or after
installation.
Operation
Your D220 is turned on using the slide switch on the right hand side of the tester.
With nothing connected, the OPEN CABLE led will light. If the D220 leds appear
dim or they fail to function, simply replace the 9-volt alkaline battery in the rear.
When you connect the D220 to a thinnet cable, it first checks to see if the cable is
“live” by looking for Ethernet packets. If network traffic is seen, the LIVE CABLE
led will light and no further tests will be performed.
If the cable is “open” (or unconnected) and no terminators are seen, then the
OPEN CABLE led will light.
If the cable or one of the BNC connectors is shorted, then the SHORTED CABLE
led will light.
The CABLE OK led will light if the cable’s continuity is good and the D220 remote
terminator is seen at the other end of the cable.
Note: The D220 remote terminator is simply a 75 Ohm terminator which is
recognized by the D220 and used for testing purposes only. It should not be
confused with the 50 Ohm terminators that are used at each end of an installed
thinnet cable.
The 50 Ohm terminators themselves may be tested by simply plugging one into
the D220. If they are with 2% of fifty Ohms, then the 50
Ω
TERMINATOR led will
light. If you connect the D220 to an installed cable which has a 50 Ohm
terminator installed at each end, then the 50
Ω
TERMINATOR and the CABLE OK
leds will both light together.
If any unusual resistance conditions are seen that don’t match one of the
scenarios described above, then the OPEN CABLE and the SHORTED CABLE leds
will light together. This suggests that some fault exists that the D220 cannot
identify and may require the use of a more sophisticated tester.