Specifications

13-9

Troubleshooting

Clock Loss Troubleshooting

If the clock frequency shown on the display is incorrect or if the CLK LOSS indicator is lit

on either the Error Detector or Pattern Generator, suspect that one of the following is

faulty:

• Clock Source module

• Display.

NOTE The CLK LOSS indicator will be lit if the clock signal is typically

<-10 dBm.

Clock Source Output

Access the Clock Source setup on the Display, check that the Clock Source Output is set

to ON. Check that the frequency of the Clock source has been set within the range of the

system, 1 GHz to 12.5 GHz for Agilent 71612 option UHx systems. If correct, use an

Oscilloscope or Power Meter to check the output level is >−10 dBm. If good, the Clock

Source is good.

Data Loss Troubleshooting

The DATA LOSS indicator is lit on the Error Detector when no data transitions have been

detected over a 1 ms period. Normally, if there is a loss of input signal the SYNCH and

ERRORS indicators will be lit. A loss of clock signal may also cause the DATA LOSS

indicator to light, see CLK LOSS Troubleshooting.

To troubleshoot the systems first check the data being applied to the Error Detector and

use known good cables - if still faulty then suspect the Error Detector.

NOTE The Error Detector DATA IN port is very sensitive and will trigger on

background noise.