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Measure db – GW Instek GDM-8261A User manual User Manual

Page 59

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ADVANCED MEASUREMENT

59

Select reference
resistance

To change the reference resistance,

press the Up/Down key. The new
resistance appears in the 2nd display.

The following is the resistance list.

2

4

8

16

50

75

93

110

124

125

135

150

250

300

500

600

800

900

1000 1200 8000

View result in
Watts

When the reference resistance is less than 50Ω, it is
possible to calculate the watt value. If the reference

resistance is greater than 50Ω then this step can be
ignored.

To calculate the power, press the
Shift key followed by the

/

key

again.

/ EXIT

SHIFT

/

dBm

Watt result
appears

W

dB

S

DC

m

W

W

Indicates W measurement

16Ω

2nd display indicates the reference
resistance

Deactivate
dBm/W
measurement

To cancel the dBm/W

measurement, press the Shift key
followed by the

/

key, or simply

activate another measurement.

/ EXIT

SHIFT

/

dBm

Measure dB

Background

dB is defined as [dBm−dBmref]. When the dB

measurement is activated, the GDM-8261A calculates the
dBm using the reading at the first moment and stores it

as dBmref.

Activate dB

Press the Shift key followed by the
Hz/P key. The 1st display shows dB,

and the 2nd display shows the
current Voltage reading.

/ EXIT

SHIFT

Hz/P

dB