Rohde & Schwarz R&S SMU200A, Service Manual

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Troubleshooting R&S SMU200A
1007.9845.82 3.38 E-6
Troubleshooting - Module IQOP3
This module consist of two submodules in one housing. Internal digital modulation signals are fed from
DACIF module via motherboard over connectors X172for path A and X182 for path B. The submodule
RFM, Radio Frequency Module contains the RF path including the wideband I/Q-modulator. The
submodule LCM, Level Control Module, contains a DSP based level control and the baseband input
circuitry
Internal adjustments “Adjust Level”, “Adjust I/Q Modulator”
A comprehensive test of the module is to run the internal adjustments.
Error Error correction
Internal adjustment “Adjust Level” or
“Adjust I/Q Modulator” aborts.
Check for correct input signals, if incorrect, first repair
feeding modules.
Adjustment aborts again:
See section “ Troubleshooting with Internal Adjustments .
Input and Output Signals
Connector,
System Signal
name Setting on Generator Frequency Level Signal flow
X263, SMP QEXT max 0.5 V Q modulation signal from
front panel or BBIN
X264, SMP IEXT max 0.5 V I modulation signal from
front panel or BBIN
X265, SMP UDET6 >3000 MHz dc 0.5 to 15 V from IQOP6
X266, SMP LCON6 >3000 MHz dc 0.5 to 8 V to IQOP6
X271, SMA IQ6 >3000MHz, I/Q modulation on >3000 MHz >-5 to 0 dBm to IQOP6
X272, SMA SYNRF 200 to 3000 MHz 200 to 3000 MHz
13
±
3 dBm
from SSYN
X273, SMA REF1040 <200 MHz 1040 MHz
10
±
2dBm
from SSYN
X274, SMA OPU3RF 0.3 to 3000 MHz, 8 dBm 0.3 to 3000 MHz 8 to 18 dBm to SATT3 or IQOP6