Agilent Technologies 8719D User Manual page 337

Next, a short circuit termination whose response is known to a very high degree is used to
establish another condition (see Figure 6-40).
The open circuit gives the third independent condition. In order to accurately model the phase
variation with frequency due to fringing capacitance from the open connector, a specially
designed shielded open circuit is used for this step. (The open circuit capacitance is different
with each connector type.) Now the values for E nv, directivity, Esr , source match, and Em,
reflection frequency response, are computed and stored (see F'igure 6-41). This completes the
calibration procedure.
Figure 6-39. Measured Effective Directivity
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