Instruction manual

3 Display 23
Main Window Display Considerations
Recorded data has two important dimensions: length and height. The length is the Time axis
and the height is the Amplitude. Each of these has its own set of controls
Managing
Display Time
The events recorded using DataTrax2 software may occur over varying time frames. For
example, recording the discharge curve of a 9-Volt battery could take hours, while recording the
QRS complex in a human electrocardiogram might take only a fraction of a second. DataTrax2
software allows the recording of both very slow and very fast events while displaying the
recorded results in a format that is easily interpreted. To manage the time display in the
DataTrax2 software, we use a parameter called Display Time. Display Time is the amount of
time represented by one full screen of data. When the program opens, the default Display Time
is set to 10 seconds. Display Time can be changed by using the display controls in the toolbar
(Figure 3-4 on page 23), or by manually entering a Display Time in the place provided at the top
of the Channel page of the Preferences dialog window, which is launched by selecting Prefer-
ences under the Edit menu.
Clicking the Half Display Time icon (big mountain) halves the screen time. If you clicked this
icon once, a 10-second full-screen display would become a 5-second, full-screen display. This
doubles the screen resolution, but cuts the amount of data seen on the screen in half. Clicking
the Double Display Time icon (little mountain) doubles the screen time. In this case, a 10-
second, full-screen display would become 20-seconds wide. This reduces the screen resolution
by half, but doubles the amount of data that you see on the screen. Clicking the Zoom Between
Cursors icon fills the display with the data located between the cursors.
Figure 3-4: Display Time icons in DataTrax2 Main window toolbar.
Limits Using the Double Display Time control compresses the data. The display time can be
doubled as many times as requested until the limit of the maximum size of the data file or
1,000,000 data points is reached.
Using the Half Display Time tool expands the record as many times as requested. But, the
DataTrax2 program will not display less than 10 data points on a screen of data.
Double-clicking the Display Time area at the top of the Main window resets the X-axis time
display to the default value originally entered on the Channel page of the Preferences dialog
window.
Examples Here are two examples demonstrating the use of the Display Time feature. In the first
example (Figure 3-5 on page 24), a human electrocardiogram is recorded with a 160-second
screen time. Notice that the record is compressed and it is impossible to resolve detail in
individual events. By clicking Half Display Time five times, the screen time is reduced from 160
seconds to about five seconds, making individual events clearly visible.