ATL TELECOM USER GUIDE
AM2048A OS/OM
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i.e. the link is too long or there is interference in the cable.
b) If clock clips are occurring the timing mode may not be set correctly. The likely cause is
that in the “Configuration>User Port” screen the timing is set to ‘internal’ whereas the
timing should be set to ‘transparent’ to lock to the incoming clock.
3
If CRCs are enabled and only one copper pair is being used for transmission, ensure that
the idle pattern is set correctly in the “Configuration>User Port” Screen.
The front panel loops appear not to work
With the management terminal connected at the ELU, go to the “Test > User Port” screen.
See that the Front Panel Enable is checked.
Use F8 to view the NTU configuration, again, see that the Front Panel Enable is checked.
Check that no conflicting tests are already activated.
How do I get back to the factory settings?
Go to the “Configuration>Software” menu.
Select the ‘Default Config.’ option.
Use the TAB key or the arrow keys to place the cursor in the box.
Press spacebar to select the option.
Press ‘Enter’.
The unit will pause for a few seconds before re-booting.
The factory default for the desktop unit is an NTU.
For persistent problems please contact your local distributor for assistance.
Atl telecom Transmission technical support is available by fax on +44 29 20 500 850 in the
first instance.
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ATL TELECOM USER GUIDE
AM2048A OS/OM
Check the fibre connections to see if they are all clean.
If the equipment is connected to a very long line near to the limit of operation, it is possible
that one or more of the circuit ends can work error free whereas another end might have a
high bit error rate.
There are no alarms but data transfer is not happening
For all interface types
1
Check that no test loops are active. (The front panel TEST LED should be off on all units).
2
Go to the “Configuration>Timeslot Map” screen. Check to see that the Network
Timeslots (nTS) and the Customer Timeslots (cTS) are suitable for your application.
Pressing F5 will restore the timeslot map to its default setting.
For X.21/V.35
1 Check that the interface is in the correct mode, i.e. DTE or DCE. The user interface
module has hardware links that may be used to change the setting. The factory default
setting is DCE. When connecting the AM2048 to terminal equipment, either the AM2048
must be set to be a DCE and the terminal equipment to a DTE or vice versa. The setting of
the links may be checked without opening the box by going to the “Information>System”
screen.
2
Does the connected V.35 DTE implement RTS? If not, go to the “Configuration>User
Port” screen and use the circuit clamps to ensure that the AM2048 will accept data.
Note
: For V.35
Circuit 105 = RTS Request to send.
Circuit 106 = CTS Clear to send.
Circuit 107 = DTR Data terminal ready.
Circuit 109 = CD Carrier detected.
3
Check that the interface has been set to the correct speed. Go to the
“Configuration>User Port” screen and check the value of N (x64) and the given data rate,
matches the rate expected by the connected data terminal. If there is a doubt, go to the
Configuration> User Port Screen and press ‘Enter’.
4
When the AM2048 is configured as a DCE and if the connected DTE provides a TX clock,
go to the “Configuration>User Port” screen and select the “DTE clock enable” option.
For data terminals that do not provide a clock, try using the “Invert Receive Clock’.
This will change the position at which the receive data is sampled and may help if cable
clock skew is a problem.
For G.703
1
Check that the G.703 port configuration matches that of the connected equipment.
2
Check the “Performance>User Port” screen
a) If Bipolar violations are occurring there could be problems with the receive data path,
