Agilent Technologies 54845B Manual page 92

Chapter 5: Troubleshooting
Power Supply Trouble Isolation
Check +15 V Bias and Remote Inhibit cabling.
E
If the oscilloscope will not power up, check all cabling to troubleshoot and correct the problem.
Figure 5-4 shows the routing of the +15 V Bias and Remote Inhibit signals from the front panel
to the power supply. The power supply is on only when the remote inhibit signal is between
+1 V and +5 V. A problem could be caused by a faulty cable or bad connector anywhere in this
path. Check all the cables and connections and replace any at fault.
Figure 5-7
+15 V Bias
Routing of +15 V Bias and Remote Inhibit Signals
Replace the power supply.
F
1 If the +15 V bias is correct, but the instrument will not power up with a 196-220Ω resistor,
2 Re-assemble the instrument and apply power.
Check for the oscilloscope display onscreen.
G
1 You should see the oscilloscope display (see figure 5-2). If not, see the No Display Trouble
2 If you see the display, return to the Primary Trouble Isolation Flowchart.
5–14
Front Panel Power
Switch
A17 Cursor Keyboard
A18 Front Panel Keyboard
1
1
A10 YUCA Interface Card
55
55
A1 Acquisition Board
9
A2 Power Supply
replace the power supply. Chapter 6 explains how to remove and replace the power
supply.
Isolation Flowchart.
W20
3
W12
3
49
W3
49
11
W1
Remote Inhibit
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