Agilent Technologies 8163A User Manual page 91

How to Measure Power Power Measurement
See Table 7 on page 93 for more details.
Figure 49 Out of Range - Power Greater Than Upper Power Limit
If the measured power is more than 40 dBm less than the range
setting, it is impossible for power to be displayed. The power value, -
1.--- dBm, as shown in Figure 50, is shown. This means that the
measured power is greater than the resolution at this [Range] value.
You must increase the [Range] value.
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Agilent 8163A/B, 8164A/B, and 8166A/B User's Guide, Fourth Edition