Make a selection using the vertical band tool 
.
On the Shortcut (right-click) menu, click Graph Ping.
The Ping graph is a line plot of data values against depth for all data points in a single ping or a selection of pings.
To display a ping graph for a single ping:
Point at the required ping.
On the Shortcut (right-click) menu , click Graph Ping.
To display a graph for a selection of pings:
Make a selection using the vertical band tool .
On the Shortcut (right-click) menu, click Graph Ping.
Note: For angular position variables, each ping will produce two lines on the graph, one for the minor-axis angle, the other for the major-axis angle.
This feature is available for Sv variables only. It enables you to plot on the Ping graph the TVG function based on a user-defined value for Sv at R = 1m.
One application of this feature is to estimate the background noise level in your data. See Figures 15 and 16 of the Echoview Technical Manual for further information about this technique.
To display the Constant-Power Curve:
Display a ping graph.
On the Shortcut menu, select Show Constant-Power Curve.
The curve is affected by the Absorption on the Calibration page of the Variable Properties dialog box for the variable.
The value of Sv at R = 1m can be adjusted on the Shortcut menu. Right-click on the Ping Graph and adjust the Constant-Power Curve Value.
The algorithm is:
where:
Y = Constant-Power algorithm value evaluated at R (m).
Value_at_R = 1m = Value for Sv at R = 1m as specified on the Shortcut menu of the Ping Graph.
x = 20 (the TVG range coefficient for Sv Output)
R = The corrected range R (m) of the datapoint. The TVG range correction factor is specified on the Calibration page of the Variable Properties dialog box.
a = Absorption coefficient (dB/m) specified on the Calibration page of the Variable Properties dialog box.
Depth values are calculated according to the data's Transducer geometry and algorithms on About Depth and Range.
