SPX SPIDAR NIC-500s Operation Manual page 55

with the associated channels. The Window Time Shift is set for the selected Ports, framed by a
blue border, and the First Break is set for the selected channel, framed by a red border. If there
is more than one NIC-500, select the first NIC-500 from the drop-down menu at the bottom of
the screen
At the top of the screen is an icon with the letter 'i' in a circle. The text beside this icon displays
useful information about what is happening at each step, and which channels it's affecting.
Below that is a dialog box titled "Channel Information"; this describes the details for the
transmitter-receiver pair currently being scoped.
On the main scope window, the + and – buttons can be used to zoom in and out on the vertical
scale. Below this window, the Time Window value is displayed. The maximum Time Window
that can be displayed in Scope Mode is 500ns, even if the actual Time Window is longer.
Despite seeing a shorter time window, the entire time window is still being scoped.
Auto is generally the preferred method of setting both the Window Time Shift and First Break.
Use Start to skip the automated search and set Window Time Shift and First Break manually.
Note: Auto may fail if high frequency transducers are being employed, the antenna separation is
large, or there is a large amount of external noise. In that case, try raising the antennas or
transducers slightly off the ground to allow a stronger air wave to travel between the units.
For the NIC500-P (Figure 4-30):
1. Select Ports 1&2.
2. Press Auto. The system will initiate a search to attempt to set the Window Time Shift and
the First Break for Ports 1&2.
3. If there is a need to manually adjust, select the radio button for Window Time Shift or
First Break and use the arrows above the scope window to adjust their positions. More
Figure 4-30: Scope mode for NIC-500P
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SPIDAR Software