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Oscilloscope Menu
With the oscilloscope menu you can analyze signals and
even manipulate them in order to handle challenging
applications.
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QStar UFM sets all necessary parameters for the
signal processing. When manipulating signals
these settings will change. This might result in
a loss of signals and/or failure in measurement.
The changes done in the oscilloscope menu
might remain valid even when leaving the menu.
To get settings from QStar UFM the site should
be setup again.
QStar UFM only works with the signals within the measur
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ing window. The measuring window represents a certain
period of time which is analyzed by QStar UFM about
signals. The measuring window can be moved back and
forth by using the arrow buttons.
FIGURE 66:
Measuring Window
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QStar UFM tries to set the measuring window so that
only the desired signal (for example, V-mode) is visible.
FIGURE 67:
Oscilloscope Menu Showing Desired Signals
Use ZOOM-/ZOOM+ buttons, to scale-up/scale-down
the measuring window (decrease/increase the time the
window is open). Use arrow buttons to move window left
or right (opens earlier/later).
QStar UFM only uses signals within the window. If you
move the window, the signal will disappear and you might
get wrong/no measurement.
Information about starting point (“delay”) of measuring
window displays (Figure 50). In this picture, window
starts at 154 µSec. Use arrow buttons to change this
starting time.
Signal Analysis Using Oscilloscope
The oscilloscope allows quick check of signal quality.
This helps to get accurate measurements. Good signal
to noise ratio and “sharpness” of signals are important
for best results.
Signal-to-noise ratio (SN)
SN indicates the difference of amplitudes between the
desired signal and the noise. The higher the SN the bet-
ter the signal processing. Figure 68 shows good signals
with very good SN.
FIGURE 68:
Oscilloscope Menu Showing Good Signals
There is almost no noise at all and a clear and distin-
guished signal.
Figure 69 shows a noisy signal with lower SN. Screen
shows noise around the signal which reaches 20-40%
of signal.
FIGURE 69:
Oscilloscope Menu Showing Noisy Signal
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QStar UFM is able to handle noisy signals thanks
to its sophisticated signal processing. However,
if a high SN is encountered, the user should use
caution in case of additional interferences.