HCD-E1 Installation & Operation Manual Chapter 5 - Troubleshooting and Diagnostics
01/01/01 08:15 Diagnostic Tests 5-25
Figure 5-6 LP L CH 1 Loopback
LP R CH X
This remote loopback towards the DTE connected to data channel X of the
remote HCD-E1 (X can be one or two) is performed by connecting the local
data channel receive signal to its transmit input, as shown in Figure 5-7 for
the loop on channel 1. The test signal is provided by the DTE connected to
the data channel of the remote HCD-E1, which must receive its own
transmission without errors while the loopback is activated.
Figure 5-7 LP R CH 1 Loopback
This test fully checks the user data link, including the cables connecting the
DTE to the remote unit, the transmission path connecting the two units and
the circuits of the local HCD-E1. During the loopback, the DTE connected
to the tested data channel of the local HCD-E1 continues to receive data.
LP R R CH
This remote remote loopback towards the DTE connected to the data
channel of the local HCD-E1, is performed by connecting the transmit signal
of this data channel of the remote HCD-E1 to the input of its receive path
within the data channel interface circuits, as shown in Figure 5-8 for the loop
on channel 1. The test signal is provided by the DTE connected to the data
channel of the local HCD-E1, which must receive its own transmission
without errors while the loopback is activated.