Furuno FSV-84 manual Viii

SAFETY INSTRUCTIONS
4.6	Measuring Range and Bearing to a Target		4-11
4.7	Eliminating Weak Echoes		4-12
4.8	Suppressing Bottom Tail		4-14
	4.8.1	Adjust AGC	4-14
	4.8.2	Decrease pulse length	4-15
	4.8.3	Adjust 2nd AGC	4-15
	4.8.4	Adjust Near AGC	4-16
4.9	Suppressing Bottom and Sea Surface Reflections in Shallow Waters		4-17
4.10	Rejecting Sonar Interference and Noise		4-18
	4.10.1	Identifying noise source	4-18
	4.10.2	Interference rejector	4-18
	4.10.3	Changing Tx interval	4-19
	4.10.4	Shifting TX frequency	4-19
	4.10.5	Noise limiter	4-20
	4.10.6	Echo average	4-20
	4.10.7	Reverberation reduction	4-20
	4.10.8 Suppressing gain of bottom echo		4-20
	4.10.9	Suppressing sidelobes	4-20
4.11	Adjusting Beamwidth		4-21
4.12	Tracking a Fish School (target lock)		4-22
	4.12.1	Selecting target lock type	4-22
	4.12.2	Fish school tracking mode	4-23
	4.12.3	Position tracking mode	4-24
	4.12.4	TARGET LOCK menu	4-25
4.13	Detecting Fish Schools Aurally		4-26
	4.13.1	Selecting direction	4-26
	4.13.2	Selecting audio sector	4-27
	4.13.3	Reverberation	4-27
4.14	Offcenter		4-28
	4.14.1	Manual offcenter	4-28
	4.14.2	Automatic offcenter	4-29
4.15	Fish Alarm		4-30
4.16	Comparing Fish School Concentration		4-32
4.17	Measuring Fish School Speed		4-33
	4.17.1	Entering fish marks	4-33
	4.17.2	Deleting fish marks	4-34
4.18	Event Mark, Own Ship Position Mark		4-35
	4.18.1 Entering an event mark		4-35
	4.18.2 Entering an own ship position mark		4-36
	4.18.3 Deleting an event mark, own ship position mark		4-36
4.19	Net Course Mark		4-38
4.20	Observing Net Behavior		4-39
4.21	OTHERS Menu		4-40
	4.21.1 Displaying the OTHERS menu		4-40
	4.21.2	OTHERS menu description	4-41
4.22	Interpreting the Slant Display		4-44
	4.22.1	Bottom echoes	4-44
	4.22.2	Fish schools	4-45

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