NorthStar Navigation NorthStar 491 manual Using the More key, Changing the advance speed

Using the MORE key

Pressing the MORE key accesses the following functions:

•alarms (described in Chapter 7)

•advance speed

•A-scope

•data (numeric and graphic information on the ECHO screen)

•snapshots (961/962 only)

•video overlay setup (957/958 only)

When the menu function is in use in the 961/962, the ECHO screen moves every half second, giving the picture a less than smooth appearance. Press RETURN to go back to the main screen for a normal smooth appearance.

Changing the advance speed

Advance speed refers to the speed at which the vertical scan lines move from right to left across the ECHO screen. There are five advance speeds (plus the STOP 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 averaged over 2, 4, or 8 pings.

To set the advance speed:

1.At the ECHO screen, press MORE, then press ADVANCE SPD.

2.At the SET ADVANCE SPEED window, keep pressing the ADVANCE SPD key to select the desired advance speed.

3.Press RETURN to go back to the ECHO screen.

Page 42 491 Echo Sounder Operations Manual