User manual

SIGLENT
SDM3055 Digital Multimeter 69
dB
Each dB measurement is different between the input signal and a stored
relative value, with both values converted to dBm. The dB function applies to
AC voltage and DC voltage measurements only.
Press →【dB/dBm On】and select【Function dB】to enter the interface
shown in the following diagram.
Diagram 2- 61 dB Function Interface
Table 2- 25 dB Measurement Function Menu Function Description
Function
Menu
Settings Description
dB/dBm On/Off Turn on or turn off dB or dBm function.
Function
dB
Open dB function and the lower right corner of the
main display show “dB”.
Ref R Set the parameter via direction keys: 50Ω ~ 8000Ω.
dB Ref
Value
Set the referred value of dB.
Measure
Ref Value
Set the referred value of measurement.
Done Save all changes and return to the higher level menu.
The computation method of the dB:
dB = 10 x Log
10
[(Reading
2
/ R
REF
) / 0.001W] – (dB setting value)
R
REF
expressed measuring the resistance value in the actual electric circuit.
Range of the dB setting value: -120 dBm ~ +120 dBm. The default is 0 dBm.
dB value:
 Input a value in dB setting interface by direction button, and then store it as
dB setting value.
 Settings of dB value are stored in volatile memory.