Furuno 1823C Manual Sounder Operation, Selecting the manual mode, Selecting display range

4. VIDEO SOUNDER OPERATION

4.4Manual 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.

4.4.1Selecting 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.

4.4.2Selecting 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.

Default sounder ranges

Range 1	Range 2	Range 3	Range 4	Range 5	Range 6	Range 7	Range 8
							ETR-6/10N	ETR-30N
15 ft	30 ft	60 ft	120 ft	200 ft	400 ft	1000 ft	4000 ft	4500 ft
5 m	10 m	20 m	40 m	80 m	150 m	300 m	1200 m	1500 m
3 fa	5 fa	10 fa	20 fa	40 fa	80 fa	150 fa	650 fa	900 fa
3 P/B	5 P/B	10 P/B	30 P/B	50 P/B	100 P/B	200 P/B	700 P/B	900 P/B

4.4.3Adjusting 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.

Gain too high Gain proper Gain too low

Examples of proper and improper gain

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