Hioki DT4282 - 3.4 Decibel Conversion (dBm;dBV)

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Decibel Conversion (dBm/dBV)
3.4 Decibel Conversion (dBm/dBV)
The result of the AC voltage measurement is decibel-converted
for the standard and then displayed. For details on the conversion
formula, see “Decibel conversion measurement” (p. 93).
dBm For the voltage measurement, the “power ratio” for power 1 mW by
the standard resistance is decibel-converted and then displayed.
(Cable loss)
dBV For the voltage measurement, the “voltage ratio” for the standard
voltage 1 V is decibel-converted and then displayed. (Voltage gain)
3
4
Red
Black
1
2
Amplier
Electric
telecommunication line
Transmitter
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
10
Press SHIFT once: dBm
Press SHIFT twice: dBV
Changing the standard impedance of the dBm conversion
抵抗
FILTERREAD
MEM
COPY: MEAS_DCAdBm インピーダンス変更導通ショート交流電流 ( クランプ入力 )
0adj 後オートホールドマニュアルレンジクランプ（レンジ設定）
Standard impedance
selection range (p. 93)
1
Turn on the power while pressing
.
2
/ (Select a desired value.)
3
(Conrm the value.)
The measurement display reappears.
Even after the power is turned off, the setting
is retained.
([dBm] or [dBV] lights up)
In the case of [dBm]
OVER
レンジオーバーCOPY: MEAS_
4-20
dBV
COPY: MEAS_
dBm
HOLDRANGE過負荷検出
OVER
最大入力範囲超え
ΔＴRELMAXSLOW
Frequency
In the case of [dBV]
OVER
レンジオーバーCOPY: MEAS_
4-20
dBV
COPY: MEAS_
dBm
HOLDRANGE過負荷検出
OVER
最大入力範囲超え
ΔＴRELMAXSLOW
Frequency
Example: Measuring the [dBm] cable loss
1
2
3
4
5
6
7
Appx. Ind.
HIOKI DT4281A981-08