Fluke ScopeMeter 190 Series III, Руководство по обслуживанию

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190 Series III
Service Manual
20
2. Set the 5502A to source an 8 ms time marker (MODE marker).
3. Select the Test Tool setup:
a. Reset the Test Tool.
b. Use
j
and
k
to select manual vertical ranging, and set the Input A sensitivity range to
5 V/div (10:1 probe) or 500 mV/div (probe A factor is 1:1).
c. Use
V
to change the time base to select manual time base ranging and lock the
time base on 10 ms/div).
d. Use
N
to move the trace to the left. Once the trigger point is shifted across the left
hand border of the display, going off display, the trigger delay time with respect to the
first vertical grid line is indicated in the lower right of the display. See Figure 6 .
Adjust the trigger delay time to 8.000 ms (A

| 8.00 ms).
Figure 6. Time Base Verification
e. Use
V
to set the time base on 10 μ s/div .
f. Use
N
to move the trace to the right until the indicated trigger delay is 7.940 ms .
g. Examine the rising edge of the time marker pulse at the height of the trigger level
indicator top. Verify that the rising edge is at the center grid line. The allowed deviation
is ±3 pixels. See Figure 6 .
Input A, B, C, D Trigger Sensitivity Test
To test the Input A trigger sensitivity:
1. Connect the Test Tool to the 5502A. See
Figure 5 .
2. Reset the Test Tool to select the Test Tool setup.
3. Use
k
and
j
to change the sensitivity range to select manual sensitivity ranging and lock
the Input A sensitivity range on 2 V/div .