#### Alternate

Activates or deactivates the operating mode where the analyzer performs only one partial measurement
per sweep
.

- In normal sweep mode (Alternate disabled), the analyzer completes the necessary sequence of partial measurements at each sweep point and obtains the result (measurement point) before proceeding to the next sweep point.

- Alternate reverses the order of partial measurements and sweeps: A partial measurement is performed at all sweep points (partial sweep) before the hardware settings are changed and the next partial measurement is carried out in an additional sweep.

The Alternate mode is also valid during a system error correction.

Advantages of both sweep modes, alternative settings

If the settling time between adjacent frequency points is larger than the settling time between the partial measurements, then the Alternate measurementis faster than a normal sweep so that a smaller sweep times can be set. On the other hand, an Alternate measurement provides a result only during the last partial sweep.

Use the Alternate mode to increase the accuracy of measurements on DUTs with long level settling times (e.g. quartzes, SAW filters). To measure DUTs with short settling times and obtain a trace from the beginning of the sweep, deactivate the Alternate mode.

As an alternative to activating the Alternate mode, it is possible to insert a Meas. Delaybefore each partial measurement and thus improve the accuracy. The delay slows down the measurement.

Relation to trigger settings

In triggered measurements, Alternate has no effect if the triggered measurement sequence is identical to a single sweep point. The following table shows how the analyzer performs a sweep comprising m sweep points, assuming that each of them requires n partial measurements.

Triggered Meas. Sequence | Alternate On | Alternate Off
Sweep | Trigger event starts n partial sweeps over all sweep points. | Trigger event starts m complete measurements at consecutive sweep points.
Sweep Segment | Trigger event starts n partial sweeps over the next segment. | Trigger event starts complete measurements at all consecutive sweep points in the segment.
Point | All partial measurements of each sweep point are carried out one after another. | All partial measurements of each sweep point are carried out one after another.
Partial Measurement | Each partial measurement is carried out for all sweep points. | All partial measurements of each sweep point are carried out one after another