Agilent Technologies E5070B, User Manual

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516 Chapter 15
Measurement Examples
Measuring an Unbalanced and Balanced Bandpass Filter
Step 1. Set the port reference impedance of port 1 on the DUT (unbalanced) to 50
Ω
.
Setting Description Key Operation
Reference impedance of test port 1: 50
Ω
-
Fixture Simulator
-
Port Z conversion
-
Port 1 Z0
-
Step 2. In order to set the impedance of the differential mode of port 2 on the DUT (balanced) to
200
Ω
, set the impedances of two unbalanced ports before conversion each to 100
Ω
.
Setting Description Key Operation
Reference impedance of test port 2: 100
Ω
Port 2 Z0
-
Reference impedance of test port 3: 100
Ω
Port 3 Z0
-
NOTE
Always set the reference impedances of the two test ports before balanced conversion to
the same value.
Step 3. Turn on the port reference impedance conversion function.
Setting Description Key Operation
Port reference impedance conversion: ON
Port Z Conversion
(turns it
ON
)
The reference impedance of the command mode of port 2 on the DUT is set to 50
Ω
. The
impedance of the differential mode of that port may be set and modified independently of
setting the two-port reference impedances before balanced conversion. For more
information, see “Converting Reference Impedance of Balanced Port” on page 300.
Figure 15-30 shows the results of port reference impedance conversion.
Figure 15-30 Results of port reference impedance conversion