Simrad ARGUS FMCW 3G, Руководство пользователя

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Radar presentation and video processing | Argus Radar Operator Manual
50% of the radius, anywhere on the screen and in this case the label indicates “PPI Offcentre”.
The operator cannot offset the centre when the radar display is set to the longest range scale
(96 NM).
The centering of the PPI can be changed by means of the PPI section (OFF CENTRE and CEN-
TRE buttons), of the keyboard, or by selecting PPI mode by means of the SKs. Once PPI mode
is selected, placing the trackball cursor on the PPI, the Help line will change to “Offcentre”,
“Select” and “PPI Centre”.
Therefore, selecting Offcentre (pressing the left SK with the pointer in the PPI), the radar
picture will change the centre and the label will display “PPI Off Centre”; and vice versa, when
the radar picture is Offcentre, and the operator wants to place own ship back in the centre, he
must press the right SK, in order to perform the PPI Centre function, reading on the label “PPI
Centre”.
When in True Motion mode, the PPI CENTRE pushbutton is disabled and the Off Centre mode
is automatically selected.
P reset/TM reset
The function of the Presentation Reset button is to reset own ship position in the PPI,
see “P reset/TM reset” on page 62.
Gnd Stab/Sea Stab
Choose between sea and ground stabilization, by pressing the “Log Water Speed” (or “Log
Ground Speed” labelled button). Selecting Ground stabilization next to the speed value “SOG”
will be indicated, instead of “STW” for Water stabilization. If there is no speed data, SOG or STW,
available, the messages described in table “List of wrong operation messages” on page 133
will appear in the wrong operation messages.
Heading line and PPI graphics on/off
Pressing this button, the Heading line and all the syntethic graphics on the PPI (range rings,
maps etc.) will be hidden. The button is mono-stable, so releasing it, the PPI graphic is visual-
ized again; therefore, the button must be kept pressed to keep the PPI graphic invisible.
Tune
The function of this control is to tune the radar receiver to have maximum target returns on
the screen. In the system, two modes of tuning are available: Manual Tuning and Automatic
Tuning. To quickly toggle between manual and automatic tuning, press the TUNE knob on the
keyboard for 2 seconds.
Automatic tuning
Placing the trackball pointer on the tune progress bar, the Help line will change accordingly,
(see “Video processing section” on page 65). If the tuning adjustment mode is not already
automatic, pushing the centre SK, the tuning is switched to automatic and “TUNE” will be pre-
ceded by “A – “. In automatic tuning, at every range scale change, the transceiver performs a
tuning of the receiver itself. Should the auto tuning fail for some reason, the message “Manual
Tuning Required” is displayed, and after a few seconds it will automatically switch to manual
tuning.
To switch from automatic to manual tuning, repeat the above procedure, pressing again the
centre SK in the progress bar (the Help line will indicate “Manual” in the centre SK), or press the
TUNE knob on the keyboard for 2 seconds.
Manual tuning
The tuning progress bar indicates the tuning level of the receiver, measuring the received
signal. The adjustment is performed placing the trackball cursor over the tune progress bar,
the Help line will change accordingly. To increase the tuning voltage, the right SK must be
pressed. To decrease it instead, the left one is used, or press and hold the TUNE knob on the
keyboard. During the adjustment, the value is indicated by a small, down-oriented red arrow;
when between 48 and 52% the color is changed to yellow (see following pictures):
It is better to perform the manual tuning only in case of failure of the automatic tuning. The