Agilent Technologies 66000A, Service Manual, Page: 22 / 53

22 Troubleshooting
If You Experienced Other Problems with the Mainframe
If you experienced problems other than a selftest failure with the mainframe, proceed directly to Figure 4-1- Overall
Troubleshooting.
Troubleshooting Flowcharts
The following troubleshooting flowcharts are provided to help you identify and isolate a problem to a specific circuit on the
Main (Al) board. Once a problem has been narrowed down to a specific circuit, suggestions are provided as to the
components that may be responsible for the problem. Refer to the schematic diagrams for detailed information on circuit
wiring and component function.
The overall troubleshooting flowchart (Figure 3-1) will identify most of the problems in the mainframe. The flowcharts of
Figure 3-2 and Figure 3-3 will identify problems in the bias circuits and in the microprocessor circuits.
To aid in troubleshooting, the GPIB address switch (S7) can be set to run various test routines as described in the flowchart.
Placing a jumper on test header J5 is also required to configure and run certain tests. You must provide jumper clips for test
header J5.
Also, oscilloscope waveforms are provided on the flowchart along with the settings required to generate the waveforms.
Connect the A1 board to ac mains through an isolation transformer when making measurements with an
oscilloscope.
The Backplane (A2) board contains no active components. The schematic diagram provides point-to-point wiring
information of the connectors on the Backplane board.