Rohde & Schwarz FSQ series, Quick Start Manual

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Quick Start Guide 1313.9652.62 - 02 5.17
R&S FSQ Basic Measurement Examples
Measuring Signal Spectra with Multiple Signals
4. Set the resolution bandwidth to 100 kHz.
➢
Press the RES BW MANUAL softkey and enter 100 kHz .
It is no longer possible to clearly distinguish the two generator signals.
Fig. 5-7 Measurement of two equally-sized RF sinusoidal signals with a resolution
bandwidth which is larger than their frequency spacing.
The resolution bandwidth (RBW) can be reduced again by turning the rotary knob
counterclockwise, thus yielding a higher frequency resolution.
5. Set the resolution bandwidth to 1 kHz.
➢
Turn the rotary knob counterclockwise until the bandwidth indicates 1 kHz.
The two generator signals are shown with high resolution. However, the sweep time
becomes noticeably longer (600 ms), since it increases at a rate of 1/RBW
2 . At smaller
bandwidths (10 dB per a bandwidth factor of 10), the noise display decreases
simultaneously.
The level drop is located exactly in the center of the screen only if the
generator frequencies exactly match the frequency display of the
R&S FSQ. To achieve exact matching, the frequencies of the
generators and the R&S FSQ must be synchronized.