HP 85108, Системное руководство

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p ercen t dut y cycle pulses. The same input is applied to TRIGGER IN, and TRIGGERING
EXTERNAL is selected.
Figure 3-23.
Using External Trigger and External Modulation
PRP = 10 microseconds, Duty Cycle = 50%
Figure 3-23a is the pulse prole domain resp onse. Multiple pulses are visible b ecause the stop
time is greater than the stimulus PRP . Notice that for external triggering the minimum start
time is ab out p ositiv e 3 measuremen t resolution p erio ds with resp ect to the external trigger.
Ev en though the in ternal pulse output is not used in this particular conguration, the pulse
prole measuremen t resolution p erio d is set b y algorithm using the greater of the pulse width
and stop time.
Figure 3-23b is the frequency domain resp onse with the trigger dela y set to measure during
the On time of the pulse. One metho d used to set the trigger dela y to an appropriate v alue is:
1.
Press 4 DOMAIN 5
NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN
PULSE PROFILE , then set appropriate Start and Stop times.
2. Press 4
MARKER
5, then mov e the marker to the p oint on the pulse y ou w an t the frequency
domain measuremen t to b e made.
3. Press 4
STIMULUS MENU
5
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MORE
NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN
TRIGGER MODE
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TRIGGER DELAY .
The curren t v alue of the trigger dela y will b e display ed. No w press 4 =MARKER 5. The time
v alue at the marker will b e assigned to the trigger dela y function.
4.
Press 4
DOMAIN
5
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FREQUENCY . The trace sho ws the resp onse at the time after the TTL
T rigger In signal falling edge as set b y the trigger dela y v alue.
3-28 Operation