The Spectrum Application (RF Measurements)
R&S
®
FPL1000
254
User Manual 1178.3370.02 ─ 09
Restrictions for the R&S
FPL1000 using CISPR detectors
Specific detectors are available for EMI measurements using the CISPR filter (Quasi-
peak, CISPR Average, RMS Average). However, if any of the CISPR detectors are
used as trace detectors in a zero span measurement, the following detectors cannot be
used as trace detectors for other traces in the same display:
●
Negative peak
●
Auto peak
●
Sample
●
RMS
If you select a CISPR detector for a trace, any other active traces are automatically set
to "Auto detector", which uses the positive peak detector.
If you manually set a trace to use one of the non-CISPR detectors listed above, any
traces currently using a CISPR detector are automatically set to "Auto detector".
CISPR detectors are only available under the following conditions:
●
Trigger mode "Free Run" or "External" (trigger offset
≥
0 only for "External")
●
Gate mode: "Off"
●
Span: "Zero Span"
Dwell time
EMC tests often require a specific
dwell time
for an EMI measurement. The dwell time
defines how long the R&S
FPL1000 measures the signal at the individual frequencies.
Each detector needs a different period of time to fully charge and discharge; the indi-
vidual requirements on the dwell time are described for each detector. For details on
defining the dwell time for an R&S
Positive and negative peak detector
The maximum and minimum peak detectors display the maximum and minimum signal
level that was detected during the specified dwell time.
The minimum and maximum peak detectors are already available with the base unit.
Consider the following when defining the dwell time:
●
Unmodulated signals
: minimum time required by the detector
●
Pulsed signals
: the time must be long enough to capture at least one complete
pulse
Average detector
The average detector displays the average signal level of the samples that were collec-
ted during the specified dwell time.
The average detector is already available with the base unit.
Consider the following when defining the dwell time:
●
Unmodulated signals
: minimum time required by the detector
Measurements and Results
