Fluke 5790B, Руководство по обслуживанию

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Calibration Adjustment and Verification
Calibration Verification
3
3-63
Wideband 1-kHz Gain Verification
1. Connect the characterized 5730A wideband output with its wideband
cable to the Product wideband input.
2. Set the Product to the WIDEBAND 7V range.
3. Set the 5730A to output nominal voltage specified in Table 3-15 at 1 kHz
from the wideband output.
4. Read the measurement on the Product display and record in the
"Measured by 5790B" column in Table 3-15. Record the 5730A actual
output from Table 3-8. Calculate the error (%) in the "5790B Error"
column in Table 3-15. Populate the Lower and Upper Limit columns with
the appropriate limits based on the Specification Interval (user
selectable).
5. Proceed through the rest of the ranges in Table 3-15.
Wideband Gain Verification, 10 Hz to 500 kHz
Gain errors at frequencies other than 1 kHz can be determined by adding the
error measured at 1 kHz for that range to the error measured during wideband
flatness verification. See Table 3-17.
Wideband Flatness Verification
Proceed as follows to verify WIDEBAND input flatness:
1. Characterize the ac source by following the procedure under the heading
“Characterizing the AC Source” in the Wideband Calibration procedure,
earlier in this chapter. Use the Wideband Flatness Verification Worksheet,
Table 3-16.
2. Connect the equipment as shown in Figure 3-13.
3. The 5730A will be set to a nominal 3.2 V for all flatness verifications. The
only deviation from the nominal value will be for calibration corrections for
the 5730A and the attenuators.
4. Table 3-9 shows the combinations of attenuators required to scale the
input signal properly for each range.
5. All ranges are verified in a similar manner.
6. Obtain 8 copies of Table 3-16 with the 5730A errors recorded in the table;
one for each of the 8 voltage ranges.
7. Enter the range (7 V, 2.2 V, 700 mV, 220 mV, 70 mV, 22 mV, 7 mV, and
2.2 mV) in the box at the top of each table.
8. Enter the attenuator corrections as required for each range and add up
the errors and enter in the “TOTAL ERROR” column. The total error is the
sum of the errors of the 5730A and all attenuators used for that
frequency.
9. Proceed to verify each range by first establishing the 1 kHz reference at
the beginning of each range.
10. To establish the 1 kHz reference, set the 5730A to 3.2 V and 1 kHz. Let
the Product measure this value.
11. Push the “SET REF” softkey on the Product.