NorthStar 6000i, Quickstart Manual And Reference Manual

Page: 132 / 184

128
Reference section 6 — Echo sounding
Echo sounding alarms
Northstar 6000i
screen has a position marker. Both mark-
ers designate the same physical location.
The number of minutes of past echo data
available depends on two factors:
•
the depth of the water
•
the advance speed
In deeper water, the 490 pings at a slower
rate, so the echo sounder saves data over a
longer period of time. A slower advance
speed will have the same effect.
Echo sounding alarms
The echo sounder’s alarms work just like
all other alarms: they are displayed as a
flashing alarm icon on the screen, with
details shown on the
ALARM screen
accessed with the
STAR
key. (See Alarms,
starting on page 138.)
To alert you automatically in situations
related to echo sounding, you can set three
types of alarms:
•
fish alarm
•
seabed bottom alarm
•
temperature alarm
Setting the fish alarm
When the fish alarm is on, an alarm sounds
if an echo returns from either inside or
outside specific upper and lower limits
you’ve set.
You can selectively limit the size of the fish
you want to be notified about by adjusting
the alarm’s echo strength level. Using this
feature, you’ll only be alerted to the
presence of fish that meet your minimum
size requirements.
You may further narrow your fish alarms
to notify you of the presence of fish within
(or outside) a certain depth range. Only
those fish that are detected inside (or
outside) of that range will trigger the
alarm.
When fish are detected, the alert tone
sounds and the flashing
FISH
alarm icon is
displayed. This message clears automati-
cally after 20 seconds and the alarm is
rearmed.
To access the fish alarm settings:
1. At the
SOUNDER
screen, press
More
.
2. Press
Alarm
.