5Section 61150277L1-5, Issue 161150277L1-5A
6.Test the other B channel or additional network
ISDN devices by changing to another test (steps
3 and 4). It is not necessary to exit the test
mode to select a new test. If a new BR1TE
channel unit is selected, all DS0 tests will be
terminated.
7.To terminate the loopback, depress the TEST
pushbutton, or remove the transmit bantam
plug. Upon deactivation of the test, the
DS0-LB LED will go out.
Point-to-Point Test (CRTX, LPTX)
A point-to-point (straightaway) test can be performed
on either the U-interface (LPTX) or the E1 carrier
interface (CRTX).
To initiate a point-to-point test using a DS0 digital test
set, perform the following steps:
1.Insert the TX and RX bantam plugs of the DS0
digital test set into the bantam jack on the LIU.
Connect the clock input to the DS0 digital test
set DB-9 connector on the LIU. Configure the
test set for Near Logic and 64 kbps.
2.Select the desired BR1TE channel unit using
the DSL rotary switch on the LIU. The selected
BR1TE channel card status LED will flash
Green and Red for approximately 3 seconds
when selected.
3.Select the desired test direction, LPTX or
CRTX, on the LIU.
4.Select the desired bearer channel using B1/B2
DIP switch on the BCU.
5.Depress the recessed TEST pushbutton on the
BCU to initiate the test.
6.If the far end unit is a BR1/10 BR1TE channel
unit, perform steps 1 through 4 choosing the
same front panel switch setting. Ensure both
test sets are configured for the same test pattern
(511, 2047).
7.Observe the DS0 digital test set for bit errors.
8.To deactivate the loopback, depress the TEST
pushbutton or remove the transmit bantam
plug. Upon deactivation of the test the
DS0-LB LED will go out.
Local Loopback (LPBK)
A bilateral loopback can be initiated for any of the
BR1/10 BR1TE channel units for either bearer
channel. Since a local test pattern source is not
required for this test, it can be performed without
additional test equipment. To initiate a local
loopback, perform the following steps:
1. Select the desired BR1TE channel unit using
the DSL rotary switch on the LIU. The selected
BR1TE channel card status LED will flash
Green and Red for approximately 3 seconds
when selected.
2.Select the LPBK using the 10-position rotary
switch.
3.Select the desired bearer channel using the B1/
B2 DIP switch on the BCU.
4.Depress the recessed TEST pushbutton to
initiate the test. The DS0-LB LED will flash
once per second for a B1 loopback, twice per
second for a B2 loopback.
5.To deactivate the loopback, depress the TEST
pushbutton. Upon deactivation of the test, the
DS0-LB LED will go out.
Local Performance Monitoring
Performance monitoring of the local E1 carrier system
and the 2-wire U-interface of the ISDN data can be
performed from the front panel without interruption of
service to the customer. For this test, bearer channel
selection is not applicable and a test pattern source is
not required. To initiate local performance monitoring,
perform the following steps:
NOTE
LED indication in response to the TEST
pushbuttonasexplainedhereisinadditionto
that explained in Table 2.
1.Ensure a bantam plug is NOT installed in the
front panel TX bantam jack on the BR1/10
LIU.
2.Select the desired BR1TE channel unit using
the DSL rotary switch on the LIU. The selected
BR1TE channel card status LED will flash
Green and Red for approximately 3 seconds
when selected.
3.Select ADR1 on the LIU.
4.Depress the recessed TEST pushbutton to
initiate the test.
