Rohde & Schwarz FSMR series, Getting Started

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Measurement Examples R&S FSMR
1166.3311.12 2.12 E-2
4. Measure an unstable source (unstable in frequency)
The simulation of unstable sources requires a signal which is unstable
in the frequency domain. This signal can be simulated with active
frequency modulation on the signal generator.
The following settings are used on the generator:
1. PRESET the generator.
2. Set RF Frequency to 100 MHz.
3. Set the output level to 0 dBm.
4. Select FM Modulation, 3 kHz deviation.
5. Set the Modulation frequency to 1 kHz.
PRESET
Reset the instrument.
Press the PRESET key.
The main receiver menu is opened. The receiver mode is set.
RF LEVEL
RECEIVER
FREQUENCY
Switching to Tuned RF Level Mode
Press the RF LEVEL hotkey.
The Tuned RF level menu is displayed.
Set the measuring frequency
In the RF LEVEL menu press the RECEIVER FREQUENCY
softkey.
The frequency entry is displayed. Enter the measuring frequency
with the number keys and the appropriate unit key.
In the RECEIVER FREQUENCY entry window key in “100 MHZ”.
DETECTOR
WIDE
The measurement of an unstable signal requires the measuring
receiver to use a wide bandwidth. The FSMR offers a wideband
detector mode to acquire wideband signals with high accuracy
In the RF LEVEL menu press the DETECTOR WIDE softkey.
The wideband detector mode acquire signals with the full acquisition
bandwidth. The acquisition bandwidth (DEMOD BW) of the FSMR
can be set in the BW menu, the preset value is 12.5 kHz. The
bandwidth must be set wide enough to capture the maximum
frequency deviation of the input signal. In this example, the
frequency deviation is set to 3 kHz and the default bandwidth is 12.5
kHz.
Note: The wideband detection is not only suitable for unstable signals,
it can also be used to accurately measure modulated signals
Next steps:
The following steps will be performed as described in the previous
example (Tuned RF Level).