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Frequency Sweep Mode
For an idle quartz, the trace should be nearly symmetrical against the real
axis. The reason why it is not is as follows: We have used a cable to connect
the quartz filter to the Bode 100 and therefore we measure a phase shift of
the reflected voltage (twice the shift of the cable itself). We can remove this
unwanted phase shift by using the Impedance calibration. By calibrating the
Bode 100 we move the Impedance/Reflection reference plane to the end of
the cable connected to the input of the DUT.
5.2 Impedance Calibration
Now we perform the Impedance calibration. This type of calibration is also
described in 7.4 "Calibration in the Impedance/Reflection Mode" on page 83.
1. Click the Probe Calibration toolbar button to open the
calibration window.