ADVANCED
MEASUREMENT
39
dBm Measurement
Applicable to
Background
Using the ACV/AC mV, DCV/ DC mV or AC+DC
Voltage measurement result, the GDM-8245 calculates
the dBm value based on a reference resistance value in
the following way.
dBm
10 x log
10
(1000 x Vreading
2
/ Rref)
Parameters
Vreading
Input Voltage, ACV or DCV
Rref
Reference impedance simulating an output
load
Measure dBm
1. Activate dBm
Press the Shift key followed by the
(dBm) key.
2. dBm result
appears (the
secondary
display)
dBm
Indicates dBm measurement.
Primary
display
Indicates voltage.
Deactivate dBm
measurement
To cancel the dBm measurement,
press the Shift key followed by the
key, or simply activate another
measurement.