SWEEP Key - Receiver R&S ESCI
1166.6004.12 4.44 E-2
At least one scan is defined in the list. Two subranges are defined in the default setup. All other
parameters are shown in the following table:
Table 4-3 Default setup of scan table
Range 1 Range 2
Start frequency 150 kHz 30 MHz
Stop frequency 30 MHz 1 GHz
Step width Auto Auto
IF bandwidth 9 kHz 120 kHz
Measurement time 1 ms 100 µs
Auto ranging OFF OFF
Attenuation mode Normal Normal
RF attenuation 10 dB 10 dB
Preamplification OFF OFF
The diagram parameters to be defined are: start frequency 150 kHz, stop frequency 1 GHz, min. level
0 dBµV, grid range log 100 dB, log. frequency axis and continuous scan.
The measurement parameters correspond to the settings recommended for overview measurements to
CISPR 16.
Scan in the Time Domain
It is also possible to carry out the scan in the time domain, i.e. at a fixed frequency. Time domain
analysis is generally used to examine the time characteristics of interferences. Evaluating the detected
voltage with an oscilloscope is useful in order to correctly set the receiver measurement time. By doing
so, you can determine whether and how strongly a narrowband interference fluctuates and whether it is
amplitude-modulated or pulsed. You can also determine the pulse rate of a broadband interference. You
can set the measurement time to a value that is greater than or equal to the reciprocal of the pulse rate.
Thermostat-controlled, software-controlled and other electrically controlled instruments generate
discontinuous interferences. CISPR 14 and EN 55014 contain limit values for RFI voltage with click rate
weighting in the range 0.15 MHz to 30 MHz. Clicks can usually be measured using click rate analyzers.
However, a factor that is often critical in click rate measurements is the occurrence of successive pulses
whose individual pulse heights cannot be exactly assigned by using the time constants of the quasi-peak
weighting and can thus lead to the limit value being exceeded.
Time domain analysis can determine the pulse height and duration, which can be useful in such cases.
It meets the requirements of CISPR 16-1 with regard to accuracy of the pulse duration measurement
when the pulse duration is 10 ms and longer. Triggering can be performed internally – level set with
display line – or externally with a TTL level.
The result memory capacity is 1 440 001 measured values per trace in time domain analysis. The
measured values are stored internally and can, for example, then be analyzed by zooming in on them
with the marker. At a measurement time of 5 ms per measured value, the memory depth is large
enough to record the peak value and quasi-peak value continuously for two hours. Thus, measurement
objects such as washing machines can be evaluated for click interferences.
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