User`s guide

48 User’s and Service Guide
87050A Option K24 Troubleshooting and Block Diagram
Troubleshooting and Block Diagram
This section contains information on troubleshooting the test set to the assembly level only.
By following these procedures you should be able to determine whether the power supply,
front panel, or main switch board needs replacing. Refer to Figure 13, “Agilent 87050A
Option K24 Block Diagram,” as an aid in troubleshooting.
Theory of operation information can be found Page 28 of this manual.
General Troubleshooting Notes
WARNING The opening of covers or removal of parts is likely to expose the user to
dangerous voltages. Disconnect the instrument from all voltage sources
while it is being opened.
CAUTION If you need to disassemble the instrument, be sure to work at an antistatic
workstation and use a grounded wrist strap to prevent damage from
electrostatic discharge (ESD). See “Electrostatic Discharge Protection” on
page 56.
Troubleshooting Power Supply Problems
Turn the instrument on. Verify the condition of the LCD on the front panel:
Step 1. If the LCD is off, inspect the main fuse located in the power supply filter at the
rear of the instrument and replace if necessary.
Step 2. If the LCD is still off, there is still a possibility that the power supply is not
supplying the necessary +24V, +12V, and +5V to the main board.
Step 3. If the LCD is still off, check the cable between the main board and front panel
board.
Step 4. Finally, disconnect the DC power cable from the power supply to the main switch
board and measure the voltages. They should be +24V, +12V, and +5V. If not,
replace the power supply.