Vexilar FL-22 - Manual (Page 3)

3
abOut Flashers
How Sonar Works
SONAR stands for SOund NAvigation Ranging. Sound travels through fresh water at a
speed of approximately 4920 feet per second. A sonar device (depth finder/fish finder)
measures the amount of time a burst of energy takes to travel to the bottom and return to
the transducer. This time variation is then displayed on the readout of your sonar. When the
depth gets deeper, the time of travel for the sound increases. The burst of energy, known
as the transmit pulse, is generated by the sonar’s transmit circuitry. This burst is delivered
to the water via the transducer. The return signal , known as the echo, is received by the
receiver circuit, also via the transducer. A central processing unit makes the calculations
to determine the depth of bottom, as well as
other targets.
The sonar signal sent from the transducer will
reflect, or bounce off of any object that has
a different density than water. This makes it
possible to detect not only the lake bottom,
but also vegetation and fish.
How Flashers Work
The sonar portion of a flasher works in the
same manner as any other graph or LCD sonar device. The
difference is in how the return signal is displayed. Instead
of adding the data to a progressive representation of the
bottom to construct a history, the data on the flasher display
always represents the current point in time, also known as
“real time”. The display consists of a wheel with indicator
lights mounted in one location. The wheel is spun at high
speed and the lights turn on and off rapidly to show the
sonar readings.
The Vexilar Advantage
Vexilar’s sonar design offers an optimal balance between the power of the transmitted
pulse and the sensitivity of the receiver circuit. Excessive power has been shown to cause
premature transducer failure, distortion of the sonar signal, and possibly “spook” fish from
the audible noise they hear. Vexilar provides a balanced performance level for a wide
range of fishing scenarios.
Flasher Wheel Stationary
Flasher Wheel Spinning
Lights turn
on and off
rapidly as
wheel is
spun