Installation guide

Troubleshooting
Troubleshooting Assembly Level Problems
1-23
Troubleshooting Assembly Level Problems
WARNING Wait 30 seconds after unplugging the instrument to allow the power supplies to
discharge before removing or installing any assemblies.
Power Supplies
The power supply is a switching supply that has an automatic line-voltage and frequency selection. There are
no switches to change for 115 Vac or 240 Vac operation. The power line fuse is not replaceable. If the fuse
opens, the power supply must be replaced. To troubleshoot the signal generator’s power supplies, refer to
Table 1-12, Table 1-13, Table 1-14, and Table 1-15.
NOTE Many of the power supplies voltages shown in Table 1-12, Table 1-13, Table 1-14,
and Table 1-15 are filtered or regulated on the A23 Motherboard. In some cases, the voltage
level may be correct when measured at the A6 Power Supply, but wrong when measured at a
destination connector. If this type of situation occurs, it could be due to an open inductor, a
shorted capacitor in a filtering circuit, or a bad regulator located on the A23 Motherboard; this
would indicate that the A23 Motherboard needs to be changed.