SAEVO EVUS 8, Руководство пользователя

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6 Acquiring Images
72 Basic User Manual
0
5
50
-50
cm/s
X-axis: Time
Y-axis:
Frequency
S
Figure 6-16 Inactivated B+CW Mode 2 Imaging Screen
You can also adjust the position and angle of spectral Doppler line, and the direction of the flow cursor.
7. Select the
CW
key again to exit.
6�5�3 Optimizing Spectral Doppler Images
After activating the PW/CW mode, the imaging parameters display at the bottom of the LCD monitor, you can use
them to optimize PW/CW-mode images.
You can adjust the
Dis Format , Baseline and Angle Correct on the pop-up menu by selecting the Menu key.
NOTE:
You can adjust all parameters in the real time PW/CW mode, but can only adjust
Chroma
,
Video Invert
and
Dis
Format
in the frozen PW/CW mode.
■ Gain
PW/CW gain is used to adjust the gain of the spectrum map. Increasing the gain will brighten the image allowing
you to see more received signals with less noise.
To adjust the gain:
● Rotate the C knob clockwise to increase the value.
● Rotate the C knob anticlockwise to decrease the value.
■ Pulse Repetition Frequency
Pulse repetition frequency is used to adjust the velocity scale, filter the unnecessary low frequency signal or the
disturbance made by non-flow movements, such as breath, heart beat or sweeps of the probe.
The range of PRF value varies with the probe model and the exam type.
To adjust the pulse repetition frequency:
●
Flip the PRF switch upwards to increase the value.
●
Flip the PRF switch downwards to decrease the value.
NOTE:
The value of wall filter is also changed when adjusting PRF.