Keysight 1143A, Руководство пользователя и сервисное руководство

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To prepare the equipment
1
Turn off the front-panel power switch and remove the power cord.
W A R N I N G
When power is applied there are hazardous voltages inside the instrument.
Observe reasonable safety precautions in order to avoid injury or death.
2
Disconnect any probes from the front panel.
3
With a T10 Torx driver, remove 4 flathead screws and remove the top
chassis.
4
Check that the rear-panel line select switch is set for the correct line
voltage.
5
Connect the input power and turn on the front panel power switch.
To adjust power supply voltages
This procedure adjusts the power supply voltages. The adjustment adjusts
the
+
17.3 V supply directly. The
−
17.3 V supply tracks the
+
17.3 V supply.
Equipment Required
Equipment Critical Specification Recommended
Model/Part
Digital Multimeter Better than 0.1% accuracy 3458A
Make sure there is no load on the supplies.
Use the adjustment locator on the previous page to find the test points and
adjustments.
1 Connect the DVM between TP5 (ground) and TP1 (
+
17.3V).
2
Adjust R38 (Positive Voltage Adjust) for a reading of 17.3V
±
50 mV.
3 Connect the DVM between TP5 (ground) and TP2 (
−
17.3V).
4 Check for a reading of
−
17.3V
±
150 mV.
If the supplies cannot be adjusted into tolerance, go to the "Troubleshooting and
Repair" section of this chapter.
Service
Making Adjustments
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