Furuno 1742, 1753C 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 fixed gain setting.

The gain, range and range shifting functions used together give you the means to select the depth you can see on screen.

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 auto mode 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 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
15 ft	30 ft	60 ft	120 ft	200 ft	400 ft	1000 ft	1200 ft	1500 ft
5 m	10 m	20 m	40 m	80 m	150 m	300 m	4000 m	4500 m
3 fa	5 fa	10 fa	20 fa	40 fa	80 fa	150 fa	650 fa	900 fa
3 PB	5 PB	10 PB	30 PB	50 PB	100 PB	200 PB	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 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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