Simrad CA42 - GAIN control; Guard zone; HU - Head-Up; IR - Interference Rejection

CA42/50/52 Glossary of terms Appendix A
158
GAIN control - adjusts the gain level of the radar’s receiver. The Gain control
level is usually set for the best target presentation with a slight noise speckle in
the background on the 12 or 24nm range. The Gain control level may be reduced
on shorter ranges to improve target definition as necessary and increased on
longer ranges. Use some caution when adjusting the Gain control. If gain is set
too low, small or weak targets may be missed. If the gain is set too high on short
ranges, the CRT may become excessively covered with noise speckle making
target observation difficult.
) On the longer range scales (24nm or greater), the sea clutter control may be
advanced to decrease excessive video clutter around own ship’s position in the
center of the display if necessary.
Guard zone The use of the Guard zone feature built into the radar can detect
approaching vessels entering your “comfort” zone and you can use the guard
zone while you are moving or when anchored to protect you in a full 360
degrees.
The audio alarm can be sounded from the unit or through an external speaker/
buzzer wired into the system – see section 11.8 Electrical connections in
Installation manual.
) Warning! When you have set up a guard zone, the system generates an alarm
tone when there is an echo greater than the preset level in this zone. However,
this does not mean that the alarm tone is always generated from ships or land
alone. You may need to adjust sensitivity and set rain and sea clutter properly
after considering the effects of sea surface conditions and meteorological
conditions (rain or snow). Note also that this function does not eliminate the need
for maintaining a watch in your ship.
HU – Head-Up The heading line always appears on the display at 0 degrees as
the antenna passes the bow of the vessel. Targets appearing on the display are
relative to your own ship’s position and heading.
IR – Interference Rejection.
Lock chart cursor to radar cursor – will synchronize the two cursors in split
screen operation. The synchronization is controlled from the radar display.
Navigation points - approaching + next navigation point can be shown on the
radar display when operating in navigation mode.