Customizing G.703-Compatible Units
4-4
7925-A2-GB20-30
PRELIMINARY DRAFT
June 1997
You must reset the board for changes to the card type or loops enabled
(options 1 or 2) parameters to take effect. A system message is displayed on the
terminal to remind you to reset the board. To reset the board, use option 5 from
the Main Menu. (The board may also be reset by cycling the power on the board.)
All configuration settings are stored in nonvolatile memory.
The HDSL rate type, firmware revision numbers, and the serial number displayed
on the Board Configuration screen cannot be changed.
Options 6 and 7 (Switchpack and Line Build-Out Definitions) on the Config menu
display the switchpack and jumper positions used when changing configuration
changes manually. These options are described in later sections of this chapter.
Changing the Line Build-Out
To change the line build-out (LBO), you must move the position of four jumpers
on the board in addition to changing the Line Build-Out configuration option using
either Terminal or Switchpack Mode.
Procedure
To open the unit and change the LBO:
1.
If you are using Terminal Mode: Select option 4 (Board Configuration) from
the Main Menu, then select option 5 from the Config prompt to toggle the
LBO to the desired value.
2. Power down the unit and remove the enclosure cover, exposing the circuit
board. Use electrostatic discharge (ESD) protection when handling the circuit
board.
3. Refer to
Switchpacks and Jumpers
, Appendix C, for switchpack and jumper
locations.
4. Locate the jumper headers labeled P6 and P7.
— For 75 ohm LBO, position both jumpers on Pins 2 and 3.
— For 120 ohm LBO, position both jumpers on Pins 1 and 2.
5. Locate the jumper headers labeled C31 and C33. (These may also be
labeled P13 and P14, depending on when your board was manufactured.)
— For 75 ohm LBO, position both jumpers on Pins 1 and 2.
— For 120 ohm LBO, position both jumpers on Pins 2 and 3.
6.
If you are using Switchpack Mode: Set position 5 on switchpack S1 to either
OFF for 75 ohm LBO or ON for 120 ohm LBO.
7. Replace the enclosure cover and power up the board to reset and enable the
new line build-out setting.
