GE Vivid 7, Руководство по обслуживанию

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GE H
EALTHCARE
D
IRECTION
FC091194, R
EVISION
11 V
IVID
7 S
ERVICE
M
ANUAL
Chapter 4 - Functional Checks 4 - 53
4-3-9-5 Check Sample Volume, Compress, Reject and Frequency
Table 4-21 PW/CW Doppler Mode: Check Sample Volume, Compress, Reject and Frequency
Step Task Expected Result(s)
1. Adjust
SAMPLE VOLUME
(SV)
In PW mode, set the longitudinal size of the region to
be sampled for measurement.
Adjusting Sample volume may affect the PRF (Nyquist
limit) settings.
SV does not apply to CW mode, where the volume
sampled is the full length of the area indicated by the
cursor line.
2. Change
COMPRESS
Enables control over the contrast of the Doppler
spectrum.
When compression is raised, the spectrum image
becomes softer and some low level background noise
may appear.
Compress is available in both Live and Freeze.
3. Adjust
REJECT
Enables undesirable background noise to be removed
from the Doppler spectrum resulting in a darker
background.
Reject is available in both Live and Freeze.
4. Change
FREQUENCY
Adjusts the transmission frequency in Doppler to
control sensitivity or level of penetration.
The selected frequency is displayed in the status
window.
Adjusting Frequency may affect Sample Volume (PW)
and LVR settings.