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Maintenance 6
CALIBRATION
NOTE
To use reference sources that differ from the prompted values, see Storing
Variable Inputs later in this section.
4.After the last range is calibrated, the 8842A begins taking readings in the highest range so that you may verify its calibration. (The CAL annunciator remains on.) To verify the calibration for the other ranges, press the corresponding range button. (Pressing a function button begins the Offset and Gain Calibration procedure for that function.)
5.Repeat steps 2, 3, and 4 for the remaining functions. Note that both
NOTE
(True RMS AC option only.) The VAC and mA AC functions should normally be calibrated using reference sources at 1 kHz
6.When all functions have been calibrated, exit the calibration mode by pressing the CAL ENABLE switch and attach a calibration certification sticker over the CAL ENABLE switch. (If the True RMS AC option is installed, instead proceed to the
6-14. HIGH-FREQUENCY AC CALIBRATION
The
The reference sources used in this procedure should normally be between 90 kHz and 100 kHz. 100 kHz (nominal) is recommended. For special applications, performance may be optimized at other frequencies. See Optimizing AC Calibration at Other Frequencies, later in this section.
To perform
1.Ensure Offset and Gain Calibration has been completed for the VAC function.
2.Select the
3.Each time the 8842A prompts you for a reference amplitude, apply this amplitude to the HI and LO INPUT terminals, and press the STORE button. When STORE is pressed, the numeric display field blanks while the 8842A performs the necessary calculations. (Do not change the reference source while the display is blank.) The 8842A then displays the next prompt. For reference, all prompts are shown in Table
NOTE
To use reference amplitudes that differ from the prompted values, see
Storing Variable Inputs later in this section.
4.After the last range is calibrated, the 8842A begins taking readings in the highest range so that you may verify its calibration. To verify the calibration for the other ranges, push the corresponding range button. The CAL annunciator remains on.