NorthStar 972, Quickstart Manual And Reference Manual

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Reference section 7 — Echo sounding
Using the MORE key Northstar 972
Changing the advance speed
Advance speed refers to the speed at which
the vertical scan lines move from right to
left across the
Echo Sounder
screen. There
are five advance speeds (plus the
Off
setting, which freezes the advance of all
data):
•
2/1
- two identical lines of data are
displayed for every ping
•
1/1
- one line of data is displayed for
every ping
•
1/2
- one line of data is displayed for
every two pings
•
1/4
- one line of data is displayed for
every four pings
•
1/8
- one line of data is displayed for
every eight pings
For speeds 1/2, 1/4, and 1/8, each
displayed line of data is the average of 2, 4,
or 8 pings, respectively.
To set the advance speed:
1. At the Echo Sounder screen, press
More
,
then press
Adv spd
.
2. Keep pressing
Adv spd
to select the desired
advance speed.
3. Press
Return
to go back to the Echo
Sounder screen.
Displaying the A-scope
The echo sounder’s A-scope lets you look
closely at present or past echoes by hori-
zontally magnifying the echo from each
ping.
To display the A-scope:
1. Press
More
.
2. Press
AScope
to turn the A-Scope on or off.
The A-scope appears on the far right-hand
side of the screen, magnifying one water
column.
A-scope