Zhone Technologies IMACS-200 manual Coding, FXS port Loopbacks

the signal level, set the Tx TLP setting to a positive value (i.e., the more positive the number, the more the signal level is decreased). For example, an incoming signal at -5 dBm can be increased to -2 dBm by setting the Tx TLP to -3 dB. The Tx TLP range is -6.5 dB to +9.0 dB.

CODING

The Coding field sets the PCM companding (coding) method used for a port. Changing the coding field will apply the coding type selected to all four ports. Generally, the North American T1 environment uses u-law(mu-law) coding, and the European E1 envisonment uses a-inv. The coding default setting is defined by the type of associated WAN or OWAN port.

LB

The Loopback field lets you loop the port back toward the network and far end. The dgtl (digital) loopback sends the incoming digital DS0 signal back to the far end without decoding it. The anlg (analog) loopback sends the decoded analog signal back to the far end after decoding and then re-encoding it. Figure 6-2shows the loopback options, which allow you to test and troubleshoot the FXS port. To disable a loopback, set this field to off.

Figure 6-2. FXS port Loopbacks

FXS Ports 6-5