HP 16550A User Reference page 31

I
Probe tip assembly
Probe cable
Probing
Assembling the Probing System
Connecting Probe Cables to the Logic Analyzer
All probe cables are installed at Hewlett-Packard.
If
you need to replace a
probe cable, refer to the Service Manual that is supplied with the logic
analyzer.
Connecting the Probe Tip Assembly to the Probe Cable
To connect a probe tip assembly to a cable, align the key on the cable
connector with the slot on the probe housing and press them together.
Connecting Probe Tip Assembly
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