Telos Zephyr Xstream - Manual (Page 287)

USER’S MANUAL
Section 13: Deep Tech Information and Troubleshooting 275
13.6.1 Diagnostic Indicators
The Xstream has a number of diagnostic indicators to help in troubleshooting difficulties. They
are:
SYNC status LED
When ISDN is selected for the Interface (in the 3
rd
TEL menu), the SYNC LED (above the SEND
bargraph) should illuminate whenever power is applied. It also indicates that the Zephyr
Xstream has basic functionality. If not, the Xstream has not completed its boot cycle, or major
clock problems exist within the unit.
When V.35 is selected for the Interface (in the 3
rd
TEL menu) the SYNC LED indicates that a clock
is present at one of the V.35/X.21 digital ports, and it is at the correct frequency to match the
Bitrate (as selected in the first CODEC menu). Since this clock is passed through from the
CSU/DSU, it is the best indication that the CSU/DSU is connected and has at least basic
functionality.
When in “Ethernet” mode for Interface in the CODEC menu the sync light will generally flash
periodically for about 5 minutes after connection is established. This is due to the fact that with
Ethernet there is no master clock source as there is in V.35 or ISDN mode, so one of the units
must lock itself to the clock of the other unit. To do this without side effects the change is made
very gradually and until the process is complete the SYNC LED may flash periodically.
RECEIVE Lock LEDs
The LOCK LED illuminates to indicate that the decoder is receiving valid data. When a Receive
mode capable of independent operation using the two B channels (i.e. L3 Dual/Mono or G.722)
is used, the LOCK 1 LED indicates valid data for “Line 1” while the LOCK 2 indicates this
information for “Line 2”. When a Receive mode is used that requires 112/128 kbps of data both
LEDs illuminate once the correct pair of data‐streams are detected. Both LEDs will also
illuminate if a valid data stream is received in V.35 Single mode.
If this is flashing, or off, there is either an incorrect setting of the Receive mode, Sample Rate, or
Bit Rate (these parameters are all set in the second CODEC menu). Or, there is corrupted data
being received.
If incoming the data suffers from bit errors, the audio will be briefly muted and the appropriate
LOCK LED will extinguish until valid data is received again.
When using Ethernet mode and receiving AAC, the lock light will flicker off when bad data is
received, however error concealment may prevent the disruption from being audible in many
cases. If this is occurring frequently you may wish to check your network and/or increase the
buffering.
NT1 U sync LED
Zephyr Xstream’s built‐in NT1 has an LED on the ISDN interface card on the back of the unit.
This LED is
only applicable if you are using the Xstream's built in NT1; i.e. you are in the USA or
Canada and connected directly to the 2‐wire BRI "U" interface. Users outside the USA & Canada
can disregard this LED.