Keysight U1253B Guía Del Usuario Y Servicios página 119

4 Changing the Default Settings
Setting dB measurement
The decibel unit can be disabled by setting this to "OFF". The available options are
dBm, dBV, and OFF. For dBm measurement, the reference impedance can be set
by the "dBm-R" menu item.
Figure 4-5
118
Decibel measurement setup
Keysight U1253B User's and Service Guide