Fluke 5790B, Руководство по обслуживанию

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5790B
Service Manual
3-30
Wideband output and cable is terminated with a good 50
Ω
load. Remove
the DMM and TVC. Connect the 5730A wideband cable to the the 50
Ω
input impedance ac voltmeter in Figure 3-2. In this setup, the 50
Ω
input
impedance consists of calibrated Fluke 5790B with a precision 50
Ω
resistive load , where the load is made of carbon film resistors and
trimmed to within 50
Ω ±
200 µ
Ω
/
Ω
. The 50
Ω
load should be able to
handle as much as 3.5 V without change in resistance.
Fluke 5730A
WIDEBAND
OUTPUT
Fluke 5790B
Input 1
Type N
50
Ω
Load
elu036.eps
Figure 3-12. Wideband Calibration Source Characterization, Part 2
The Product must be used in External Guard with Guard connection between
the Product and the 5730A.
10. Measure the source output for each step in Table 3-8 and record the
measurement of the AC Voltmeter. For step in the table marked with an *, a
500 µV/V correction must be added to correct for the loading of the 50 Ω load
by the AC Voltmeter input impedance.