Performing configuration tasks
R&S
®
SGS100A
167User Manual 1173.9105.02 ─ 13
11.6 How to define the signal at the REF/LO OUT connec-
tor
The reference oscillator and the LO use the same "REF IN" connector. Hence, it is not
possible to use both an external reference source and an external LO source signal at
the same time.
The signal at the "REF OUT" connector also depends on the selected reference oscil-
lator and LO sources. The following table gives an overview of this dependency.
Table 11-1: Selection available at the REF/LO OUT connector depending on the LO and reference
oscillator sources
LO coupling source
Ref. oscillator source Int "Ext"
"Int" "OFF/REF/LO" "OFF/LO"
"Ext" "OFF/REF/LO" Combination not possible
To define the signal at the REF/LO OUT connector
1. In the "Frequency / Phase > Local Oscillator (LO) Coupling" dialog, select the "LO
Source" as required.
2. In the "Reference Oscillator" dialog, select the "Ref. Oscillator Source" as required.
3. In the "Frequency / Phase > Local Oscillator (LO) Coupling" dialog, set the
"REF/LO Output".
For dependencies, see Table 11-1.
11.7 How to prepare instruments for optimum phase
coherence
Using the LO input/output connectors, two or more instruments can be coupled to ach-
ieve optimum phase coherence between their RF output signals. The first instrument in
the chain delivers the LO signal at the "REF OUT" connector to the "REF IN" connector
of second instrument. If necessary, more instruments can be connected in the same
way. The first instrument is set such that the internal synthesizer generates the system
LO frequency.
In all following instruments, the internal synthesizer is switched off and the LO signal
from the "REF IN" connector drives the I/Q modulator or the CW path.
To connect the instruments
1. Connect the instruments as a daisy chain (see Figure 11-3), i.e. connect the "REF
IN" connector of each further instrument to the "REF OUT" connector of the previ-
ous one.
2. Optionally, provide an external reference signal for the first instrument.
How to prepare instruments for optimum phase coherence
To Next Page
Loading...
