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Calibration and Verification
Service Calibration
3
17. Press the “DO STEP” softkey and enter the 1 kHz reference value just measured
for the “APPLIED VALUE”.
18. Set the 5700A to 3.2 V at 10 Hz and adjust the 5700A to the total error value at
10 Hz for the 2.2 V range as recorded in Table 3-8.
19. Press the [ENTER] key and the system will calibrate the range at 10 Hz and step
to the 100 Hz calibration point as before.
20. Set the 5700A to 100 Hz and adjust for errors. Press “LAST ENTRY”, then press
[ENTER] as before.
21. The system will calibrate the 100 Hz point and step to the 10 kHz point.
22. Proceed through the range at each calibration point as before by applying the
proper frequency and error values.
23. All remaining ranges are done in a similar manner by installing the proper
attenuators establishing the 1 kHz reference and adjusting for errors at each
frequency.
24. When all the ranges are calibrated, store the calibration constants to complete the
calibration procedure. The rear panel CALIBRATION STORE switch must be in
the ENABLE position to store the calibration constants. Return the switch to the
NORMAL position after the constants are stored.
3-22. Service Calibration
Service Calibration is a more complete calibration that should be done only after repair or
replacement of an analog module. Service calibration is the procedure done at the factory
when the 5790A is built (However, Fluke uses an automated calibration system.)
Use the same procedure as for periodic calibration, as previously defined, except set the
rear panel CALIBRATION MODE switch to SERVICE and the CALIBRATION
STORE switch to ENABLE. This switch setting generates prompts that request many
more stimuli points than used in periodic calibration, plus the “Xfer Offset Adjustment”
and the “Wideband Amplifier Rolloff Adjustment” (the latter only if a Wideband Option
is installed). Table 3-10 lists the main input calibration steps called for in service
calibration. (WIDEBAND Service Calibration uses the same steps as the Periodic
Calibration.). Note that the “I2/I1” steps, at the beginning of AC calibration have only a
1 % absolute tolerance, but a very tight drift requirement.
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