Tektronix TDS7054, Руководство по обслуживанию

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Performance Tests
TDS7104 & TDS7054 Service Manual
4- 67
Set upper and lower
limits that ensure
triggering. Then
change limits until
triggering stops.
Figure 4- 30: Measurement of time accuracy for pulse and glitch triggering
H
Touch the
Trig When
button and select
Inside
limits.
H
Touch Upper Limit and use the keyboard to set the upper limit to
10 ns: press 10 , then n , and ENTER .
H
Touch Lower Limit and use the keypad to set the lower limit to
2 ns.
d. Change limits until triggering stops:
H
Press PUSH TO SET 50% .
H
While doing the following subparts, monitor the display (it will stop
acquiring) and the front-panel light
TRIG’D (it will extinguish) to
determine when triggering is lost.
H
Use the multipurpose knob to increase the
Lower Limit
readout
until triggering is lost.
H
CHECK that the Lower Limit readout, after the oscilloscope loses
triggering, is within 3.5 ns to 6.5 ns, inclusive.
H
Enter the time on the test record.
H
Use the keypad to return the Lower Limit to 2 ns and reestablish
triggering.
H
Touch Upper Limit ; then use the multipurpose knob to slowly
decrease
the Upper Limit readout until triggering is lost.
H
CHECK that the
Upper Limit
readout, after the oscilloscope loses
triggering, is within 3.5 ns to 6.5 ns, inclusive.