Rohde & Schwarz R&S SMU200A, Service Manual

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Baseband Digital IQ-Output (Option R&S SMU/SMJ-B18) R&S SMU200A
1007.9845.82 1.86
E-12
Internal Baseband Generator
Function Trigger and Marker
The equipment layout for generating the digital modulation signals includes the options R&S SMU-B13
(Baseband Main Module) and R&S SMU-B10 (Baseband Generator).
Test equipment - Oscilloscope (table 1-1, pos 5)
- Trigger source
Test setup
Connect trigger source to trigger input of DUT.
Connect the oscilloscope to marker outputs 1 and 2 on the front of
DUT
Test method In the Custom Digital Mod menu, a modulation with 100 kHz symbol
rate, external triggering and active marker outputs (with 50 kHz and
25 kHz) is set. Modulation is started with the external trigger. No
parameters are checked, but only whether the modulation has
triggered (query of trigger status) and whether the markers are output.
Measurement Settings on DUT
Frequency: 100 MHz
Level: 0 dBm
Custom Digital Mod:
State On
Trigger/Marker
Trigger In - Mode Armed Auto
Trigger In - Source: External
Reconfigure Marker – Channel 1: Pulse,
Divider: 2 (50 kHz)
Reconfigure Marker – Channel 2: Pulse,
Divider: 4 (25 kHz)
Apply trigger.
Check start of curve:
Display of the trigger status in the Custom Dig Mod / Trigger –
Marker _ Clock changes from
Stopped to Running
Check markers using the oscilloscope:
Marker 1: frequency 50 kHz, Marker 2: frequency 25 kHz.
Note:
Marker 3 or 1B is not measured here, but rather in the test of the
AUX-IO.
The number of necessary measurement depends on the number of installed baseband paths, see
following table:
Installed paths 1 x BB 2 x BB
Custom Digital Modulation: trigger and marker function
Number of measurements
1 x 1 x