Onwa Marine Electronics KR-1338C v.2 - Manual (Page 10)

In/Out harbour
Setting IN/OUT harbour
Enter AIS menu, select 9. In/Out Harbour , use direction key to set.
This function is used to avoid ships in the harbour because too many AIS
boats nearby may cause continuous alarm. Upon entering the port you may
select "ON" , CPA and TCPA alarm will be disabled.
8
Loss target alarm function
If the current range of AIS targets within the information given by the
maximum update interval had not yet received, will be loss target alarm
function is triggered, in this case, the target becomes the symbol shown
below loss target mark, symbol color is red and flash, while the radar alarm
will sound to remind the operator out to pay attention. To manually stop the
audible alarm, press the [SELECT/CANCEL] key once.
Figure10 loss target display symbol
How to open the loss target alarm function
Did not turn this function on the LOSS target symbol will still be displayed,
but does not trigger the alarm. Start as follows:
1. Into the AIS menu and select "10. Lost target alarm";
2. Press the arrow keys to select "On" and press the [ACQ/ENTER];
3. Press [MENU] key 2 times to exit.