User's Manual

E1 Spread Spectrum Radios
8-25
Figure 8-32: System Test (2)
8.7.1 Local Loopback
Under Local Loopback, it is easier to detect any malfunction at the E1 interface. E1 testing equipment is required
while detecting because on the execution of this function the testing signal cannot enter MOD, so it is not possible to
use PRBS to detect. This function setting is also done through the NMS or the LCD display button.
Figure 8-33: Local Loopback
In the System Test window, tick the Setting column for Tributary 1. Press Accept Setting. The IDU’s first E1
interface is now performing the Local Loopback test. There can be multiple selections for the test. Press Clear All
Test to stop all tests.