User guide

If the input signal is still out of range for any of these parameters, the error detector
will be immediately disconnected again.
Error Detector Does not Count Bits
If the analyzer does not count any bits, press Sync Now.
This might happen after the Error Detector had glitches at the clock input.
DLL Alignment Failed
If an error message containing the text "... DLL alignment failed ..." is displayed,
increase or decrease the bit rate by 1bit/s.
See “Bit Rate - Procedures” on page 141 for details on setting the bit rate.
The instrument provides several error indicators to help you identify setup
problems.
The following list contains possible causes for setup problems, sorted from the
most severe to the least severe:
PG CLK LOSS
This indicator turns red when no clock signal is detected at the PG Clock In port.
• External Clock Input is selected and the external clock is off or not connected.
• Your cables or the external clock is faulty.
ED CLK LOSS
This indicator turns red when no clock signal is detected at the ED Clock In port.
BERT connected looped back or to your device:
• The PG clock output is off or not connected.
• There is no connection to the ED clock input.
• Your cables are faulty.
9 Solving Problems
470 Agilent J-BERT N4903B High-Performance Serial BERT