Tektronix TDS6404, Руководство по обслуживанию

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Performance Tests
4- 68
TDS6000 Series Service Manual
H
Set the test signal amplitude for about three and a half divisions on
screen. Now fine adjust the generator output until the
CH 1
Amplitude readout indicates the amplitude is 350 mV. Readout may
fluctuate around 350 mV.
H
Disconnect the 50
Ω
precision coaxial cable at
CH 1
and reconnect
it to CH 1 through a 10X attenuator.
b.
Check the Main trigger system for stable triggering at limits:
H
Read the following definition: A stable trigger is one that is
consistent; that is, one that results in a uniform, regular display
triggered on the selected slope (positive or negative). This display
should
not
have its trigger point switching between opposite slopes,
nor should it roll across the screen. At horizontal scale settings of
2 ms/division and faster,
TRIG’D will remain constantly lighted. It
will flash for slower settings.
H
Press the Trigger Slope button to select the positive slope.
H
Adjust the Trigger LEVEL knob so that there is a stable trigger.
CHECK that the trigger is stable for the test waveform on the
positive slope.
H
Press the Trigger
Slope
button to select the negative slope. Adjust
the Trigger LEVEL knob so that there is a stable trigger.
H
CHECK that the trigger is stable for the test waveform on the
negative slope.
H
Leave the trigger system triggered on the positive slope of the
waveform before continuing to the next step.