Troubleshooting 4
5000 Series Oscilloscopes Service Guide 59
 
✔ The sampling speed of the oscilloscope depends on the 
time/division setting. It may be that when time/division is set 
to slower speeds, the oscilloscope is sampling too slowly to 
capture all of the transitions on the waveform. Use peak 
detect mode.
✔ Check that all oscilloscope probes are connected to the 
correct signals in the circuit under test.
✔ Ensure that the probe’s ground lead is securely connected to 
a ground point in the circuit under test. For high-speed 
measurements, each probe’s individual ground lead should 
also be connected to a ground point closest to the signal 
point in the circuit under test.
✔ Check that the trigger setup is correct.
✔ A correct trigger setup is the most important factor in 
helping you capture the data you desire. See the User’s Guide 
for information about triggering.
✔ Check that infinite persistence in the Display menu is turned 
off, then press the Clear Display softkey.
✔ Press the AutoScale key.
If you cannot see a channel
✔ Recall the default setup by pressing Save/Recall then Default 
Setup. This will ensure that the trigger mode is Auto.
✔ Check that the oscilloscope probe’s BNC connector is 
securely attached to the oscilloscope’s input connector.
✔ Check that the probe clips are securely connected to points 
in the circuit under test.
✔ Check that the circuit under test is powered on.
You may have pressed the AutoScale key before an input 
signal was available.