Tektronix DCM300, Technical Reference

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DMM800 Series Adjustment Procedures
Handheld and Benchtop Instruments Basic Service
39
2. Lift the circuit board assembly out of the top case half.
3. Set calibrator to output 100 VAC at 10 kHz (sinewave).
4. Connect the outputs of the calibrator to the
_
C V
W
and COM input
connectors of the multimeter.
5. Adjust VC3 until the display shows +98.60 V.
6. Set the calibrator frequency to 500 Hz (sinewave).
7. Confirm that the reading is less than 100.60 V. Repeat step 5 if necessary.
8. Set the calibrator frequency to 1 kHz (sinewave).
9. Confirm that the reading is less than 104.0 V. Repeat step 5 if necessary.
NOTE . Steps 10 through 17 do not apply to the DMM830.
10. Set the calibrator to output 20 VAC at 10 kHz (sinewave).
11. Adjust VC1 until the display shows 19.700 V.
12. Set the calibrator frequency to 500 Hz (sinewave).
13. Confirm that the reading is less than 20.110 V. Repeat step 11 if necessary.
14. Set the calibrator to output 2 VAC at 10 kHz (sinewave).
15. Adjust VC2 until the display shows 1.9700 V.
16. Set the calibrator frequency to 500 Hz (sinewave).
17. Confirm that the reading is less than 2.011 V. Repeat step 15 if necessary.
Reassembling the Multimeter
1. Ensure that the rotary dial is properly aligned.
2. Align the tabs of the bottom case half with the slots in the top case half at the
end of the meter near the input connectors.
CAUTION. Before closing the case, check that the rotary dial is properly aligned
and that the battery wires are not pinched.
3. Close the case, snapping the case halves together.
4. Reinstall the three screws.