Rohde & Schwarz R&S SMU200A, Руководство по обслуживанию

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Troubleshooting R&S SMU200A
1007.9845.82 3.28 E-6
Error Error correction
Always maximum output level
Check voltage of RF RMS detectors.
Freq < 3 GHz:
DIAG_IQOP3_LCM_D_UDET < 0.1 V -> IQOP3/RFM is
defective, otherwise IQOP3/LCM defective.
Freq > 3 GHz:
DIAG_IQOP3_LCM_D_UDET < 0.1 V and
DIAG_IQOP6_UDET6 < 0.1 V -> IQOP6 defective,
otherwise LCM defective.
Faulty I/Q Modulation
Before performing troubleshooting for I/Q modulation, always call “Adjust All”. If adjustment fails,
perform troubleshooting on the basis of the error message displayed.
Error Error correction
No output level with I/Q modulator
set to Internal Baseband Check output level for CW.
If not OK: proceed with section "
Level Errors ".
Setting on Vector Signal Generator:
RF ON
”Multicarrier CW” menu:
No. of Carriers = 1
Carrier Phase = 45 deg
Adopt with Accept
State = On
Measure DC voltage at I OUT and Q OUT:
DC voltage < 0.4 V: Troubleshooting on DACIF board
Measurement using Test Point s:
DIAG_IQOP3_D_LCM_IX = 0.35 V to 0.45 V
DIAG_IQOP3_D_INX = -0.45 V to -0.35 V
DIAG_IQOP3_D_QX = 0.35 V to 0.45 V
DIAG_IQOP3_D_QNX= -0.45 V to -0.35 V
If these voltages are not OK:
Baseband processing by submodule LCM of IQOP3 is
defective.
Call Hardware Debug Page “Level”.
In “LCM (DSP status, OK)” block, compare DSP measured
value “bb rms” with setpoint value “uBBRMS”.
Deviation > 10%: Baseband RMS detector on LCM is defective.
If OK: submodule RFM of IQOP3 is defective.