Manual Sounder Operation; Selecting The Manual Mode; Selecting Display Range; Adjusting The Gain - Furuno 1833 Operator's Manual

4.4

Manual Sounder Operation

Manual operation is useful for observing fish schools and bottom using a fixed
gain setting.
The gain, range and range shift functions used together give you the means to
select the depth you can see on the screen. The basic range can be thought of
as providing a "window" into the water column and range shifting as moving the
"window" to the desired depth.
4.4.1

Selecting the manual mode

1. If not displayed, press the [HIDE/SHOW] key to show the sounder soft keys.
2. Press the AUTO/D. BOX soft key to show the mode/frequency window.
3. Select OFF (MANUAL).
4. Press the RETURN soft key.
4.4.2

Selecting display range

Press the [RANGE +] or [RANGE -] key to select a range. The default ranges in
feet, meters, fathoms and passi/braza are as below. Note that the range cannot
be changed in the automatic sounder mode.
Range 1 Range 2 Range 3 Range 4 Range 5 Range 6 Range 7 Range 8
15 ft
5 m
3 fa
3 P/B
4.4.3

Adjusting the gain

Normally, set the gain to the point where excessive noise does not appear on the
screen. Use a higher gain setting for greater depths and a lower setting for
shallow waters.
Default sounder ranges
30 ft 60 ft
10 m 20 m
5 fa 10 fa
5 P/B 10 P/B 30 P/B
Gain too high
Examples of proper and improper gain
4. VIDEO SOUNDER OPERATION
120 ft 200 ft
40 m 80 m 150 m
20 fa 40 fa
50 P/B 100 P/B
Gain proper Gain too low
400 ft 1000 ft 4000 ft
300 m 1200 m
80 fa 150 fa 650 fa
200 P/B 700 P/B
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