Fluke 5820A, Руководство по обслуживанию

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5820A
Service Manual
3-54
Trigger source = ext; level = 200 mV; ext atten = x10;
slope = +; mode = auto
Measurement Function positive width
1. Program the Calibrator Mainframe to output the pulse width and period at 1.5 V as
listed in Table 3-26.
2. Change the horizontal scale of the DSO so that you can view one positive pulse
width. Record the width measurement made by the DSO. Compare to the tolerance
column of Table 3-26.
3. Change the pulse amplitude and repeat the measurements for an amplitude of 0.15
V. You will need to change the vertical scale of the DSO.
Table 3-26. Pulse Generator Verification: Pulse Width
Nominal Value
(V p-p)
Pulse Width
(s)
Period
(s)
Measured
Value (s)
Deviation
(s)
1-Year Spec.
(s)
1.5 1.0 x 10
-9
200.0 x 10
-9
250 x 10
-12
1.5 9.9 x 10
-9
200.0 x 10
-9
700 x 10
-12
1.5 79.9 x 10
-9
1.000 x 10
-6
4.2 x 10
-9
1.5 500.0 x 10
-9
10.00 x 10
-6
25.2 x 10
-9
0.150 1.0 x 10
-9
200.0 x 10
-9
250 x 10
-12
0.150 9.9 x 10
-9
200.0 x 10
-9
700 x 10
-12
0.150 79.9 x 10
-9
1.000 x 10
-6
4.2 x 10
-9
0.150 500.0 x 10
-9
10.00 x 10
-6
25.2 x 10
-9
3-54. Pulse Skew Calibration and Verification
The following equipment is used to Calibrate and verify Pulse Skew:
•
High Frequency Digital Storage Oscilloscope: Tektronix 11801 with Tektronix SD-
22/26 sampling head
•
SMA T m-f-m connector
•
3 dB attenuator, SMA (m/f)
•
BNC(f) to SMA adapter (2)
•
0.5 m SMA (m) - SMA (m) cable
•
N to BNC cable supplied with the Scope Calibrator (2)
The skew function was introduced in December 1998. It is available only in Scope
Calibrators shipped since that time. Skew calibration and verification is normally
performed as part of the pulse width calibration and verification procedure.
For these procedures, skew is measured from 30% of the trigger signal amplitude to 30%
of pulse amplitude. As an example, the trigger output is ~1.0 V into 50
Ω
, if the pulse
amplitude is 1.5 V, the skew would be measured from 450 mV point on the pulse to 300
mV on the trigger.
Put the Calibrator into standby. Connect the N to BNC cable supplied with the Scope
Calibrator to the Calibrator Mainframe’s CHAN 1 connector. Connect the other end of