Tektronix 222PS, Руководство оператора

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Auto Setup
In Detail
3Ć6
Vertical Scaling
The 222PS then determines the characteristics of the signal, so it can
produce a useful display.
The 222PS sets the vertical position to display the signal in the center
of the screen. If both channels have a signal, the 222PS displays both
signals.
The instrument also sets the volts per division to display each signal
with several divisions of amplitude.
Horizontal Scaling
If only one channel is receiving a signal, the 222PS sets the horizontal
position to display 1-5 waveform cycles. It determines the peak
values and sets the trigger level at the midpoint.
If both channels have a signal, the instrument uses the channel 1
signal to set the seconds per division and trigger level. If the two
signals are synchronized, they both appear stable. Otherwise, the
channel 2 signal is untriggered.
Low and High Frequencies
AUTO SETUP avoids the timeĆbase modes used with the slower time
scales. It therefore does not set the seconds per division to 0.1 s or
slower and does not produce a readable display for signals slower
than 20ĂHz.
For signals with frequencies above 100ĂkHz, AUTO SETUP always
uses a secondsĆperĆdivision setting of 5Ă
m
s to minimize search time.
The 222PS may display such highĆfrequency signals with too many or
too few cycles on the screen; therefore, they may appear confusing.
You may need to make small corrections to the seconds per division
knob to get a useful display.
Table 3Ć1 shows all AUTO SETUP actions.
Auto Setup
In Detail
3Ć6
Vertical Scaling
The 222PS then determines the characteristics of the signal, so it can
produce a useful display.
The 222PS sets the vertical position to display the signal in the center
of the screen. If both channels have a signal, the 222PS displays both
signals.
The instrument also sets the volts per division to display each signal
with several divisions of amplitude.
Horizontal Scaling
If only one channel is receiving a signal, the 222PS sets the horizontal
position to display 1-5 waveform cycles. It determines the peak
values and sets the trigger level at the midpoint.
If both channels have a signal, the instrument uses the channel 1
signal to set the seconds per division and trigger level. If the two
signals are synchronized, they both appear stable. Otherwise, the
channel 2 signal is untriggered.
Low and High Frequencies
AUTO SETUP avoids the timeĆbase modes used with the slower time
scales. It therefore does not set the seconds per division to 0.1 s or
slower and does not produce a readable display for signals slower
than 20ĂHz.
For signals with frequencies above 100ĂkHz, AUTO SETUP always
uses a secondsĆperĆdivision setting of 5Ă
m
s to minimize search time.
The 222PS may display such highĆfrequency signals with too many or
too few cycles on the screen; therefore, they may appear confusing.
You may need to make small corrections to the seconds per division
knob to get a useful display.
Table 3Ć1 shows all AUTO SETUP actions.