To Make dB Measurements 
Each dB measurement is the difference between the input signal and a
stored relative value, with both values converted to dBm.
dB = reading in dBm – relative value in dBm
• Select  DC V   or   AC V  .
• The first reading taken after you enable dB measurements is
converted to dBm and is stored as the relative value in the
dB Relative Register. Any previously stored value is replaced
with the new value.
• After enabling dB operations, you can edit the relative value by
pressing
 Shift   >   (Menu Recall). This takes you to the “dB REL”
command in the 
MATH MENU (only if dB is enabled). Go down to
the “parameter” level, and then edit the value displayed.
• The register is cleared when you change functions, turn dB off,
turn off the power, or perform a remote interface reset.
Enables dB operation;  
Press again to disable. 
Math annunciator is on when 
dB operation is enabled.  
To read / edit the dB relative value, use the MATH menu. 
Chapter 2  Quick Start 
To Make dB Measurements 
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