Rohde & Schwarz FSQ series, Quick Start Manual

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R&S FSQ Basic Measurement Examples
Measuring Harmonics with Frequency Sweeps
5.12 Quick Start Guide 1313.9652.62 - 02
5.3 Measuring Harmonics with Frequency Sweeps
There are advantages in performing harmonic measurements with a single frequency sweep,
provided that the harmonic distance is in a way that a resolution bandwidth can be selected
which is wide enough to give an acceptably short sweep time.
5.3.1 High-Sensitivity Harmonics Measurements
If harmonics have very small levels, the resolution bandwidth required to measure them must
be reduced considerably. The sweep time is, therefore, also increased considerably. In this
case, the measurement of individual harmonics is carried out with the R&S FSQ set to a small
span. Only the frequency range around the harmonics will then be measured with a small
resolution bandwidth.
1. Reset the instrument.
➢
Press the PRESET key.
The R&S FSQ is now in the default state.
2. Switch on the internal reference generator.
➢
Press the SETUP key.
➢
Press the softkeys SERVICE - INPUT CAL .
The internal 128 MHz reference generator is now on. The R&S FSQ RF input is switched
off.
3. Set the center frequency to 128 MHz and the span to 100 kHz.
➢
Press the FREQ key.
➢
Enter 128 MHz .
➢
Press the SPAN key and enter 100 kHz .
The R&S FSQ displays the reference signal with a span of 100 kHz and resolution
bandwidth of 2 kHz.
4. Activate the marker.
➢
Press the MKR key.
Marker 1 will be activated and positioned to the signal maximum (fundamental at 128
MHz). The level and frequency of the marker will be displayed in the marker information
field.