Fluke 5790A Service Manual page 114

5790A
Service Manual
Range
7 V
2.2 V
700 mV
220 mV
70 mV
22 mV
7 mV
2.2 mV
3-34
Table 3-9 shows the combination of the attenuators required to scale the input
signal properly for each range.
Table 3-9. Attenuators Required for Each Range
Attenuators
None
(1) 10 dB
(1) 20 dB
(1) 20 dB
(2) 20 dB
(2) 20 dB
(3) 20 dB
(3) 20 dB
4. All ranges are calibrated in the similar manner. The calibration program will
prompt you at each step as to what frequency to apply.
5. The flatness calibration program starts with the 7 V range at a frequency of
10 Hz.
6. To establish a 1 kHz reference at the beginning of each range, set the 5700A to
3.2 V and 1 kHz and set the 5790A to the 7 V range in this case. The 5790A will
measure the magnitude. Record this value in Table 3-8.
7. Press the "DO STEP" softkey and enter the 1 kHz reference value measured for
the "APPLIED VALUE".
8. Set the 5700A to 3.2 V at 10 Hz and adjust the 5700A to the total error value at
10 Hz that was recorded in Table 3-8 during source characterization.
9. Press the [ENTER] key and the system will calibrate the range at 10 Hz and step
to the 100 Hz calibration point.
10. Set the 5700A to 100 Hz and adjust the 5700A to the total error value at 100 Hz
that was recorded in Table 3-8 during source characterization.
11. Press "DO STEP" and "LAST ENTRY" keys to enter the current "APPLIED
VALUE".
12. Press the [ENTER] key and the system will calibrate the range at 100 Hz and
step to the 10 kHz calibration point.
13. Proceed through the range at each calibration point frequency in the same manner
as steps 10, 11, and 12 by applying the proper frequency and total error values
(Note that the total error value is the sum of the errors of the 5700A and all
attenuators used for that range and frequency).
14. When the calibration program has completed all the steps in the 7 V range, it will
step to the beginning of the 2.2 V range at 10 Hz.
15. Install the 10 dB attenuator as required by Table 3-9 for the 2.2 V range.
16. Establish the 1 kHz reference for this range by again setting the 5700A to 3.2 V
at 1 kHz and the 5790A to the 2.2 V range. The 5790A will measure the
magnitude. Record this value in Table 3-8.
3.2 V
1 V
320 mV
(1) 10 dB 100 mV
32 mV
(1) 10 dB 10 mV
3.2 mV
(1) 10 dB 1 mV
5790A Input