Sea Tel 4009-9 BROADBAND-AT-SEA, Руководство по установке

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Setup – Searching 4009-9 Installation Manual
10-3
satellite arc), search up along the polarization angle SWEEP INCR degrees, step two Search Increments
to the left, search down, etc expanding out in the search pattern until Search Limit is reached. When the
end of the search pattern is reached, the ACU will retarget the antenna to the calculated Azimuth and
Elevation point.
If the desired signal is found (AND network lock is achieved in the satellite modem) at this position, or
anywhere within the search pattern, the ACU will terminate search and go into Tracking mode. If the
desired signal is not found the ACU will wait SEARCH DELAY, then target the antenna to start point
shown in the graphic above and begin the search pattern again. This cycle will repeat until the desired
satellite signal is found or the operator intervenes.
10.1.3. No Gyro Search Pattern
If the ship does not have a gyro compass to use as a heading input to the Antenna Control Unit, you may
manually key in the actual heading of the vessel and then re-target the desired satellite, every time you
need to re-target a satellite, or configure the ACU to do a “No Gyro Search Pattern”.
You configure the ACU to use this pattern by using the following settings:
SEARCH INC - set to the default value for the frequency band that your antenna model is
currently being used for (typically 15 counts).
SEARCH LIMIT – leave this set to the default value.
SEARCH DELAY – default, or any number of seconds from 1-255 that you would prefer that the
ACU wait before starting an automatic search.
SWEEP INC – Larger antennas should have slower speeds and smaller antennas should have
faster speeds:
Larger antennas should have slower speeds set to 0047 (= 5 degrees/second) for 2.4M
to 3.6M antenna systems).
Mid size antennas can be driven a little faster, set to 0063 (= 8 degrees/second) for 2M
antennas models).
Smaller antennas should have faster speeds, set to 0079 (= 18 degrees/second) for all
0.8M to 1.5M antenna models).
GYRO TYPE – MUST be set to zero for this search pattern.
SAT REF mode – MUST be ON for this search pattern.
Target any satellite longitude value which includes even tenths digit values (ie SAT 101.0 W or SAT 101.2
W). If the desired satellite longitude includes an odd tenths digit, you must round it up, or down, one
tenth to make the tenths digit EVEN. The Antenna Control Unit calculates the Azimuth, Elevation and
Polarization values it will use to target the antenna. However, without heading input, the ACU cannot
target a “true azimuth” position (relative to true North). It will target the antenna to the calculated
elevation and a repeatable “Start” relative azimuth position. In Series 04 antennas this relative position
will be 90 degrees away from the nearest mechanical stop. In all other antennas it will be 000 degrees
relative.
Initially the antenna will go to the “Start” relative azimuth position at the calculated elevation. Then the
antenna will search up 450 degrees in azimuth, search up one Search Increment in elevation, search
down 450 degrees in azimuth, search down two Search Increments in elevation, etc until Search Limit is
reached. When the end of the search pattern is reached, the ACU will retarget the antenna back to the
start point shown in the graphic below.
If the desired signal is found (AND network lock is achieved in the satellite modem) at this position, or
anywhere within the search pattern, the ACU will terminate search and go into Tracking mode. If the
desired signal is not found the ACU will wait SEARCH DELAY seconds and then begin the search pattern
again. This cycle will repeat until the desired satellite signal is found or the operator intervenes.