Press the button HORI MENU in the control panel. Press F1 to select the 
Extended Window . Under the Extended Window mode, the screen is 
divided into two display areas as the above picture shows.  The upper part 
displays the original waveforms, which can move left and right through 
rotating the knob horizontal POSITIONAL or can enlarge and reduce the 
selected areas through rotating the knob horizontal SCALE. The lower part 
displays the horizontal scale waveform. Note that scale time base improves 
definition compare with the main time base (as the above picture shows). 
Because the waveforms displayed by the whole lower part are corresponding 
to the areas selected by upper half part, rotating the knob horizontal SCALE 
to reduce the selected areas can improve the scale time base, namely, can 
improve the waveforms horizontal SCALE multiple.
Note: The max scale time base is 200ns/div.
4.3 Trigger Release
Trigger release can observe complex waveforms (such as pulse series). 
Release time is the time for the oscilloscope to re-enable the trigger. In 
the period of release and suppression, the oscilloscope will not be triggered. 
For example, a set of pulse series, which is required to trigger on the first 
pulse, can set the release time to the pulse width.
Press the HORI MENU button to enter the level control menu. Use the 
Multipurpose knob to select trigger release.
Chapter 5 - Mathematical Operation 
UTD2000CEX-II series oscilloscope carries a variety of mathematical 
operations: 
 Math: Source 1+ source 2, source 1- source2, source 1* source 2, 
     source 1/ source2 
 FFT:Fast Fourier Transform
 Digital Filter
Press the MATH button to enter the mathematical operation menu.The 
POSITION and the SCALE knobs can be used to change the vertical 
position and the vertical profile of the mathematical operations. Under 
mathematical operations, the horizontal position cannot be independently 
adjusted, it will change automatically according to the analog input channel 
signals.
5.1 Mathematical Function
Press MATH button, then press F1 to choose the type (math)
Math Menu
Descriptions
Set any one of the Ch1,
CH2 as Math Source 1
Source 1 + Source 2
Source 1 - Source 2
Source 1 * Source 2
Source 1 / Source 2
Set any one of the CH1, 
CH 2 as Math Source 2
Options
Math
CH1, CH2, 
+
-
*
/
Ch1 CH2,
Functions
Type
Source 1
Operator
Source 2
UTD2000CEX-II User Manual