Notes for Using the Echo Sounder
ix
Notes for Using the Echo Sounder
·
The life of the echo sounder depends on the hours of use. Put the device on the rest even during a short time
by turning off the power switch every time the set is unused.
·
The use of the echo sounder with a large output produces noises that interfere itself.
It is recommendable that the echo sounder is used after reducing the output with the output decreasing unit
instead of lowering the sensitivity by the sensitivity controller of the receiving amplifier.
·
In the case of a echo sounder that can emit two or more frequencies, use it by selecting the frequency that
will minimize the noises to itself using the frequency selector.
·
A long transmission pulse may impair the range resolution of the image.
In the case of a echo sounder with a pulse selector, be sure to use it by selecting a shortest possible pulse.
·
A wide angle of directivity of the oscillator may cause the set to catch noises, locate the fish erroneously, or
decrease the power of the ultrasonic wave to be emitted in the required direction. In the case of a echo
sounder with a frequency selector, be sure to select a higher frequency so as to set the narrowest possible
angle of directivity.
·
Fishing grounds are common assets for every fisher. Each ship must refrain from emitting any ultrasonic
wave in the direction that may give trouble to other ships. Be sure to use a horizontal echo sounder, in
particular, so that it does not disturb the operation of the echo sounders of other ships.
