Scientific SMO1000A-S, User Manual

Page: 41 / 176

User Manual SMO1000A-S
41/176
Adjust Horizontal Scale
Turn the HORIZONTAL Scale Knob on the front panel to adjust the horizontal time base.
Turn clockwise to reduce the horizontal time base and turn counterclockwise to increase.
The time base information at the upper left corner of the screen will change accordingly
during the adjustment. The range of the horizontal scale is from 2ns/div to 50s/div.
The Horizontal Scale Knob works (in the Normal time mode) while acquisitions are
running or when they are stopped. When running, adjusting the horizontal scale knob
changes the sample rate. When stopped, adjusting the horizontal scale knob lets you
zoom into acquired data.
Adjust Trigger Delay
Turn the Position Knob on the front panel to adjust the trigger delay of the waveform.
During the modification, waveforms of all the channels would move left or right and the
trigger delay message at the upper-right corner of the screen would change accordingly.
Press down this knob to quickly reset the trigger delay.
Changing the delay time moves the trigger point (solid inverted triangle) horizontally and
indicates how far it is from the time reference point. These reference points are indicated
along the top of the display grid.
All events displayed left of the trigger point happened before the trigger occurred. These
events are called pre- trigger information, and they show events that led up to the trigger
point.
Everything to the right of the trigger point is called post- trigger information. The amount of
delay range (pre- trigger and post- trigger information) available depends on the time/div
selected and memory depth.
The position knob works (in the Normal time mode) while acquisitions are running or when
they are stopped. When running, adjusting the horizontal scale knob changes the sample
rate. When stopped, adjusting the horizontal scale knob lets you zoom into acquired data.
Set Roll Mode
Press the Roll button to enter the roll mode.
In Roll mode the waveform moves slowly across the screen from right to left. It only
operates on time base settings of 50 ms/div and slower. If the current time base setting is
faster than the 50 ms/div limit, it will be set to 50 ms/div when Roll mode is entered.
In Roll mode there is no trigger. The fixed reference point on the screen is the right edge
of the screen and refers to the current moment in time. Events that have occurred are
scrolled to the left of the reference point. Since there is no trigger, no pre- trigger
information is available.
If you would like to stop the display in Roll mode, press the Run/Stop button. To clear the
display and restart an acquisition in Roll mode, press the Run/Stop button again.
Use Roll mode on low- frequency waveforms to yield a display much like a strip chart
recorder. It allows the waveform to roll across the display.