Rohde & Schwarz R&S UPP, Руководство пользователя

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Instrument Functions
R&S
®
UPP
463 User Manual 1411.1055.32 ─ 10
If no stable measured value is detected during this time, the measurement is aborted.
An invalid measured value is output in the numeric display, the sweep and also via the
remote line.
Defining a timeout is important especially with the "true" settling methods, because,
with these methods, a settled value may never be detected if tolerance limits are too
narrow. If averaging is employed, on the other hand, the number of measurements,
and thus the measurement time, are finite and the timeout may be deactivated, as it
were (by entering the maximum value of 2000
s).
Note: If a multichannel analyzer is used, max. 1.44 million samples can be monitored.
In these analyzers, the maximum timeout is therefore dependent on the sampling rate
and the analog bandwidth; at 40
kHz analog bandwidth, for example, it is 15 s.
Remote command:
SENSe[1]:FUNCtion:SETTling:TOUT
on page 772
5.38.4 Settling for Start Conditions (Event-Triggered Measurements)
The settling procedure can also be applied to all event-triggered measurements – i.e.
measurements that are measured-value-triggered rather than time-triggered.
With external sweeps, the sample signal never changes simultaneously with the start
of the frequency or level measurements that monitor the sample signal for changes. In
the event of a value change, therefore, the monitoring routine usually does not mea-
sure the new frequency or level value but an intermediate value, i.e. a value between
the old and the new value. If the trigger threshold (variation) is smaller than the actual
value change, it may happen that even the measured intermediate value triggers the
next measurement in a sweep. This does not produce a falsified measured value (Y
value of the sweep display) since the next measurement is not started until the signal
change is detected. However, the sweep parameter (X value of the sweep display) that
triggers the next measurement is too close to the preceding X value.
To ensure that the X values of an external sweep are also measured with great accu-
racy, the settling procedure should be applied to external sweeps as well.
Due to a frequency change, some DUTs take a long time until the level has settled
(e.g. hearing aids with a sound level limiter or compander/expander circuits with short
level rise times and long decay times). With such DUTs, therefore, it is not sufficient to
apply the settling procedure to the trigger routine only. In addition, then, a start delay or
Function Settling should be activated.
Timeout monitoring is not meaningful in settling procedures applied to event triggers
(i.e. not time triggers), since it takes an indefinite period of time until the external event
triggering a measurement occurs, and an early abortion of the monitoring routine would
be of no avail.
If a multichannel analyzer is used, max. 1.44 million samples can be monitored. In
these analyzers, the maximum time for detecting (and settling to) the external trigger
condition is therefore dependent on the sampling rate and the analog bandwidth; at
40
kHz analog bandwidth, for example, it is 15 s.
Settling Methods