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side of the display can be wrong if too much (or too little) power is used.
The usual rule of thumb is to increase the power level and/or receiver gain
until you can just start to see a “double bounce”.
A double bounce is where you see a second return from the bottom at
twice the actual depth. This is due to the sonar signal traveling back to
the surface and being reflected again back to the bottom and back to the
depth transducer a second time. In shallow water with hard bottoms
having good reflectivity it is often possible to see second, third and even
fourth bounces if too much power is used.
Display Threshold
The Color Bar is divided into 16 parts. The lower part has the value of 1
and the top part has the value of 16. The acoustic signal is digitized to a
value from 1 to 16. When a screen pixel representing an acoustic signal
is painted onto the display screen it is painted in the color representing
the signal strength. A very weak signal might be painted in dark blue, a
stronger signal in green and a very strong signal in red. There are a number
of predefined color bars and you can also create your own color bar with
colors of your choice.
The Display Threshold slider determines whether a signal response gets
drawn on the display screen or is ignored. If the strength of the signal is
greater than the display threshold it is painted on the display screen in the
color determined by the Color Bar. If the signal of that particular pixel of
data is weaker than the Display Threshold then that pixel is ignored and
not drawn on the display screen.
AScope Threshold
TheAScopeThreshold slider determines whether a signal response gets
drawn in the AScope area of the screen (if the AScope is turned ON) or
