Rohde & Schwarz SMU200A - Switch-On Problems

R&S SMU200A Troubleshooting
1007.9845.82 3.15 E-6
Switch-On Problems
• Error: Unit cannot be switched on.
Action Possible error causes and further steps
Check power-on switch on the rear
C
heck fuses on the rear

Power switch OFF: Switch on power supply.
Check yellow LED (standby).

LED remains unlit:
 Measure voltage at X211.A17 (slot 5A):
Rated value: +12 V ± 1 V
Voltage OK: Keyboard membrane or controller
faulty.
No voltage: Subsequently remove DACIF (slot 6D),
SSYN A (slot 4A) and SSYN B (slot 5A;
two-path instruments only).
 Repeat measurement of voltage at X211.A17 (slot
5A).
Rated value: +12.0 V ± 0.1 V
Correct voltage: The removed module caused short
circuit and is to be replaced.
No voltage:
 Check voltage regulator on motherboard:
To do so, first measure voltage output at power
supply. This is accessible from outside through
housing grille at rear left, at flat cable connector ,
upper edge of power supply, 3
rd
pin from left:
Rated value: +13.5 V ± 0.3 V
No voltage: Power supply faulty
Correct voltage: voltage regulator on motherboard
faulty.