Teledyne T3DMM4-5, Руководство пользователя

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dBm
The dBm function is logarithmic and based on a calculation of power delivered
to a reference resistance, relative to 1 mill watt. This function only applies to AC
voltage and DC voltage measurements.
Press → [ dB/dBm ] → [ On ] and select [ Function dBm ] to enter the interface
displayed in diagram 2- 60.
Diagram 2- 60 dBm Function Interface
Table 2- 24 dB Measurement Function Menu Function Description
Function
Menu Settings Description
dB/dBm On/Off Turn on or turn off dB or dBm function.
Function
dBm Open the dBm function and the lower right corner of the
main display will display “dBm”.
Ref R Set the parameter via direction keys: 50Ω ~ 8000Ω.
Done Save all changes and return to the higher level menu.
The computation method of the dBm:
When the dBm function is turned on, the measured value of voltage is
transformed into dBm according to the following formula.
dBm = 10 x Log
10
[(Reading
2
/ R
REF
)/0.001W]