HP 54620A, User'S And Service Manual

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If you can’t see a channel
Check that the analyzer probe cable is securely connected to the input
connector. The key on the probe cable should be facing down.
Check that the analyzer probe lead wires are securely inserted into the
connector assembly and that the grabbers make good contact with the
probe lead wires.
Check that the grabbers are securely connected to the nodes in the
circuit under test.
Check that the circuit under test is powered on.
You may have pressed Autoscale with no input signal available.
Performing the checks described above ensures that the signals from the
circuit under test are seen by the analyzer.
Check that the threshold setting for the analyzer inputs is correct for the
logic family in use in the circuit under test.
If there is no activity on the channel activity indicators, the ground lead may
not be connected, the threshold setting may be incorrect, or there may be no
activity on that signal in the circuit under test.
Check that the desired channels are on.
1
Press On/Off.
2
Make sure the selected desired channels are on by using the Entry
knob or Select knob to scroll through the channels. Then press On for
each channel that should be on, but is off.
Use Autoscale to obtain an automatic setup for all channels.
Solving Problems
If you can’t see a channel
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