Fluke 5500A, Service Manual

Page: 182 / 296

5500A
Service Manual
6-56
6-69. Pulse Width Verification
The following equipment is used to verify the pulse width.
•
High Frequency Digital Storage Oscilloscope: Tektronix 11801 with Tektronix SD-
22/26 sampling head
•
3 dB attenuator, 3.5 mm (m/f)
•
BNC(f) to 3.5 mm(m) adapter (2)
•
BNC cable supplied with the SC600
•
second BNC cable
Refer to Figure 6-7 for proper setup connections.
Connect the BNC cable supplied with the SC600 to the Calibrator Mainframe’s SCOPE
connector. Connect the other end of the BNC cable to one BNC(f) to 3.5 mm(m) adapter
then to the DSO’s sampling head through the 3 dB attenuator.
Using the second BNC(f) to 3.5 mm(m) adapter and BNC cable, connect the Calibrator
Mainframe’s TRIG OUT connector to the 11801’s Trigger Input. The Calibrator
Mainframe should be in SCOPE mode, with the Edge menu on the display. Press
O
on the Calibrator Mainframe to activate the output. Press the softkey under TRIG to
select the TRIG/1 External Trigger output.
Set the DSO to these parameters:
Digital Storage Oscilloscope Setup
Main Time Base position (initial) 40 ns
Vertical scale 200 mV/div
Trigger source = ext; level = 0.5 V; ext atten = x10; slope = +;
mode = auto
Measurement Function positive width
1. Program the Calibrator Mainframe to output the pulse width and period at 1 V as
listed in Table 6-43.
2. Change the horizontal scale of the DSO to the value listed in the table. Adjust the
main time base position and vertical offset until the pulse signal is centered on the
display. Record the width measurement. Compare to the tolerance column of Table
6-43.
Table 6-43. Pulse Width Verification
Calibrator Mainframe
Output
DSO horizontal
scale
11801
Reading
Tolerance
Width Period (time/div)
4.0 ns 200 ns 1 ns 0.700 ns
44.9 ns 200 ns 10 ns 2.745 ns
45 ns 200 ns 10 ns 6.250 ns
500 ns 1.25 us 100 ns 29.0 ns