1.Safety Information
dBm function represents the absolute value of the power. The function calculates
the power of the reference resistance according to the measured voltage, relative
to 1 mW:
dBm = 10 x log
10
( reading
2
/ reference resistance / 1 mW )
Press the Rel R softkey to select the reference resistance. The value may be 50
(default), 75, 93, 110, 124, 125, 135, 150, 250, 300, 500, 600, 800, 900, 1000,
1200, or 8000 Ω.
dB Function
dB represents the relative value which is used in the relative operation of dBm
value. When enabled, the multimeter calculates the dBm value of the reading and
subtracts the preset dB from this value and then displays the result:
dB = 10 x Log
10
( reading
2
/ reference resistance / 1 mW) - dB preset
Press the Rel R softkey to select the reference resistance. The value may be
50(default), 75, 93, 110, 124, 125, 135, 150, 250, 300, 500, 600, 800, 900, 1000,
1200, or 8000 Ω.
Press the dB Rel softkey to select the relative value.
The relative value must be
from -120 to +120 dBm
(default 0).
Relative Value
When the relative operation is turned on, the reading displayed on the screen in
relative operation is the difference between measured and preset values. The
value is specific to the present function and will persist even if you leave this
function and return to it later.
Reading = Measured value – Preset value
In the measurement function menu, press the Rel softkey to turn on or off the
relative operation.
When on, the measured value is stored as a reference value.
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