SPX SPIDAR NIC-500s Operation Manual page 46

"stacking". Stacking improves data quality because noise, which is usually a random addition to
the trace, tends to zero when averaged.
The following diagram displays how data is stacked. At each data collection point, the trace is
collected multiple times. Traces are averaged to calculate the resulting data trace, which is
saved.
Stacking improves data quality but may slow down survey time. The more stacks, the longer it
takes to collect data at each survey position. It is important to find the ideal number of stacks
that adequately detect the target. Select the number of stacks from the drop-down box. Stacks
values will always be 2
maximum value of 32,768.
Note: Stacks must be set the same for the GPRs on a single NIC-500. Stacks can be
different between NIC-500s on a daisy chained system.
NIC-500X
There are some restrictions when using a NIC-500X, with antennas connected to GPR1 and
GPR2:
•
Both GPRs must have the same number of stacks
•
Both GPRs must have the same number of points per trace (time window / sampling
interval). See Figure 4-20.
•
Points per trace must be an integer
If the above restrictions are not followed, a warning message will pop up with the user tries to
save the configuration.
n
, where n=1 to 15. This translates to a minimum value of 2 to a
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SPIDAR Software