Instrument Function
R&S
®
SMF100A
200
Operating Manual 1167.2319.02 ─ 12
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Switch off the RF power source for zeroing, but do not disconnect it from the power
sensor. This proceeding keeps the thermal equilibrium, and the zeroing process
also compensates the noise that superimposes the measured signal (e.g. from a
broadband amplifier).
Remote command:
Source
Selects the source for measurement.
"RF"
Measurement source is the RF signal of the generator. The RF fre-
quency is used as the measurement frequency of the sensor and the
corresponding correction factor is used.
In this mode the RF frequency of the generator is send to the sensor
automatically if changed.
"User"
Measurements source is any freely selectable source. The frequency
is entered manually under frequency (e.g. for measurement of ampli-
fier gain with 2 sensors).
Remote command:
Frequency
Source User only
Enters the frequency for measurement source "User".
Remote command:
Level Offset
Activates and defines a level offset which is added to the measured value. This allows
e.g. an attenuator in the signal path to be considered. The offset is always entered in
dB, irrespective of the selected unit for result display.
Remote command:
:SENSe<ch>[:POWer]:OFFSet:STATe
Filter
Determines the length of the filter used for the measurement. The filter length affects
the measurement time directly.
The averaging filter is used to reduce fluctuations in the measured result to the extent
desired. Such fluctuations can be caused by inherent noise of the measuring instru-
ment, modulation of the measurement signal or beats from the superposition of adja-
cent carriers. A more stable display has to be traded off against longer measurements.
The measurement result is obtained from a two-stage averaging process.
Note:
Longer measurements do not mean that it takes longer to display a new result,
but rather that it takes longer for the result to settle when the power changes.
RF Level
