 | Topology Identifies the stimulus configuration that is set in the True Mode Stimulus Configuration dialog box. The following topologies and port assignments are available in 4port VNAs: • BAL-BAL: Two balanced ports (1:3):(2:4) or (2:3):(1:4). • BAL-SE: One balanced port and one single-ended port (1:3):2, (1:3):4, (2:4):1, (2:4):3, (2:3):1, (2:3):4, (1:4):2, or (1:4):3. • BAL-SE-SE: One balanced port and two single-ended ports (1:3):2:4, (1:4):2:3, (2:3):1:4, or (2:4):1:3. Note: Not all port combinations (port reversals) are listed. Port Select Identifies the port selection that is set in the True Mode Stimulus Configuration dialog box. Differential port pair selection of (1:2) or (3:4) is not valid when in TMS mode. Stimulus Identifies the stimulus that is set in the True Mode Stimulus Configuration dialog box. • Single Ended: Standard VNA mode. • TMS Drive: Balanced stimulus in both forward and reverse directions. • Reverse TMS: Reverses the port assignments (requires 4-port VNA). • Source (Ref Plane): Both sources active at the same frequency. True Mode Stimulus Config Opens the DifferentialView – True Mode Stimulus dialog to select and configure a differential stimulus measurement. Refer to the TRUE MODE STIMULUS CONFIGURATION Dialog Box. Ref. To Port Opens a dialog to select the frequency and phase offset reference port (1 through 4). TMS Phase Offset Sets the fixed phase offset that is applied to the true differential drive for situations that require stimulus compensation. TMS Power Offset Sets the fixed power offset (in dB) that is applied to the true differential drive for situations that require stimulus compensation. Phase Start Sets the starting phase offset (± 3600°) in phase sweep configuration (CW only). Phase Stop Sets the starting phase offset (± 3600°) in phase sweep configuration (CW only). |
