GSSI SIR 4000, Руководство пользователя

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Geophysical Survey Systems, Inc. SIR® 4000
Manual
MN72-433 Rev F 22
Edit Gain Curve
This menu option allows you to
modify the number of gain points
along the time-variable gain curve
and, if in Manual Gain, strengthen
or weaker individual points.
Pressing Edit Gain Curve with either
the Control Knob or Enter button
will activate the time-variable gain
curve for editing and open new
button functions for the bottom of
the keypad.
•
With the time-variable gain
curve activated, use the
Control Knob or arrow keys
to move between different
gain points.
Add Point:
Use this button to add up
to eight (8) gain points to the gain curve. These points will be evenly spaced throughout the data scan.
Erase Point:
Use this button to remove gain points from the gain curve. The minimum number of gain
points is two (2). As points are removed, the remaining gain points are evenly redistributed throughout the
data scan.
Revert:
Returns to the main Setup Screen without saving any changes to the time-variable gain curve.
Save and Exit:
Saves changes to the time-variable gain curve and returns to the Setup Screen.
When using Manual Gain you can modify the individual gain points using the following steps. Use caution
when manually adjusting gain point values. If you add too much gain to a single point it could create a false
layer in the data.
1
Press the Control Knob or Enter key to select a gain point and then use the knob or arrow keys to
adjust to strengthen or weaken the point.
2
Press the Control Knob or Enter key a second time to save and deselect the modified gain point.
Note:
The SIR 4000 is only displaying about 25% of the actual amplitude range. This means that
even if your data appears slightly clipped, the SIR® 4000 is likely still recording the full amplitude
range of the reflection. If you use a –12 dB display gain, you will see an accurate representation of
the recorded scan. This also means that when you view your data in RADAN, it will appear under-
gained and you will need to add some display gain.