Kongsberg Simrad RA83, Service Manual

Page: 39 / 210

2.2.10 System Setting
(1) Adjusting antenna height (SYSTEM/SYS SETUP/HEIGHT)
The HEIGHT setting menu is located in SYSTEM/SYS SETUP.
The purpose of this setting is to provide the most effective STC function, giving the best result
according to the height of a radar antenna. As known, the received sea clutter intensity varies
depending on the radar antenna height. Use the STC control from time to time to see if targets can
be clearly seen even if the sea clutter is in presence. If you find it difficult to discriminate the targets
in such a condition, select the most suited STC law to obtain the best result. For operational detail,
please refer to the operation manual.
Relation between the range versus STC attenuation is shown in Figure 3.1.
5
9(value of "HEIGHT")
1
Attenuation
Range
Figure 3.1 Image of "HEIGHT" value to STC curve
(2) Setting automatic/manual gain circuit (ADJUST/GAIN AUTO or MANUAL)
The GAIN setting menu is located in ADJUST/GAIN AUTO or MANUAL. Adjust the AUTO GAIN
value in AUTO GAIN mode so that the noise appears slightly on the screen.
Adjust the MANUAL GAIN value in MANUAL GAIN mode. The MANUAL or AUTO GAIN mode must
be set before entering the setting menu.
(3) Setting automatic/harbor/manual STC circuit (ADJUST/SEA AUTO MANUAL)
The STC setting menu is located in ADJUST/SEA AUTO, MANUAL or HARBOR. Adjust the AUTO
STC preset value in SEA AUTO mode so that small targets are clearly visible in the sea clutter.
Because the SEA AUTO function is designed based on the presence of the sea clutter, it is not
suited for the use in smooth waters such as harbors, inland waterways, etc. For operating the radar
in such areas, use HARBOR or SEA MANUAL mode. Adjust the HARBOR STC preset value in
HARBOR mode, and also adjust the MANUAL STC preset value in SEA MANUAL mode same as
AUTO mode. The MANUAL, HARBOR or AUTO STC mode must be set before entering the preset
value.
(4) Tuning calibration (ADJUST/AUTO TUNE )
In the tuning calibration menu, the AUTO tuning adjustment is provided.
Adjust the AUTO tuning so that long-range targets are clearly visible. This adjustment allows the
AFC (Auto Frequency Control) system to be tuned in to the center IF, which is performed by
controlling the bias voltage for a variable-capacitor diode in the AFC circuit.
(5) Resetting to the factory default
When you have changed the software or need system reset to recover from the malfunction caused
by the software hang up, you should carry out the factory default setting. To do so, press the
"MENU" key and "PANEL" key simultaneously when turn on the radar.
CAUTION:
When the system is defaulted, all user preset parameters such as the transmission timing, ship’s
heading direction, accumulated operating hours will be reset to an initial value.
Keep recording the manufacturing number, settings, and operating hours on a paper while the radar
is in service.
93842105-00
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