Fluke 990DSL, Руководство пользователя

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XDSL Testing and Loop Qualification
The XDSL Toolbox
5
5-33
test requires a generic transmitter at the far end of the pair such as a CopperPro
Series II or Terminator II tester. The far-end device must be instructed to
transmit the desired single frequency at a level of 0 dBm, at an impedance of
100 or 135 Ohms.
Note
For measurement accuracy, the sending device’s frequency should be
as close as possible to an integral multiple of 4.3125 kHz. If the
sending device is a CopperPro tester or Terminator, it automatically
rounds off the entered frequency to the nearest bin frequency to
ensure accurate results. Unlike the DSL Auto-Test, the WB Loss test
is manually controlled. There is no communication between the
sending and receiving units.
Setting Up a WB Loss Test
Select the Target Service Type (ADSL/2, HDSLx, ADSL2+, VDSL (12 MHz)
or VDSL (18 MHz) in the setups menu (Table 5-5). The measurement
Termination Impedance will automatically be set to 100 or 135 Ohms,
depending on the Target Service Type selected.
Table 5-5. WB Loss Test Setup Parameters
Parameter Setting (default in bold)
Target Service Type ADSL/2 (1.1 MHz), HDSLx (1.1 MHz),
ADSL2+ (2.2 MHz), VDSL (12 MHz), VDSL
(18 MHz)
Termination Impedance 100
Ω
or 135
Ω