NF FRA51602, Instruction Manual

Page: 141 / 286

4.2 Simple operation for the first use
4
-
11
FRA 51602
4) Press the
MEASURE DOWN
key on the front panel to perform a sweep measurement and wait until the
measurement is completed.
5) Turning the knob moves the marker on the measurement data. You can read the gain or phase at any
frequency. You can also detect maximum values, search, find the location of an arbitrary gain value, and
perform other such operations. For more information on the operations, read "
5.6 Marker operations
".
4.2.4 Measuring impedance
Impedance is defined as the ratio of the voltage and current of the device under test (DUT). The current of
the sample is converted to voltage using a shunt resister. By measuring the voltage of the shunt resister and
the sample simultaneouly, the impedance of the sample can be obtained. An impedance of 1 Ω is displayed
on the screen with a multiplier of one (0 dB).
Figure 4-6 Example of connections for measuring impedance
The voltage of the DUT current i × Rs is input to CH2 from the current detection resistance Rs. By setting
the CH2 input weight coefficient to 1/Rs and measuring the ratio of CH1 and CH2, the impedance value
can be read directly as the gain (ratio voltage and current). For more information on the input weight
coefficient, read "
5.9.2 Input weighting
".
1 ～
2
Current detection
resister
Rs
i
i x Rs
v
DUT
Zx