Sea Tel DAC-03, Инструкция по установке и эксплуатации

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DAC-03 Tracking Antenna Controller Operation
2-13
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
– set to 192 if your antenna is a Series 04 or Series 06. Set to 193 if your
antenna is a Series 97, Series 00 or Series 07. This parameter sets the sweep increment
(shown in the graphic above) to be +/- 4.0 degrees above/below the satellite arc.
GYRO TYPE – must NOT be set to zero.
SAT REF
mode – may be
ON
if you are experiencing frequent, or constant, gyro read
errors (error code 0001). Must be ON if you are using NMEA Gyro input.
Target the desired satellite longitude value but include an odd tenths digit (ie if you desired to
target inclined satellite 186.0 W you would key in SAT 186.1 W for the ACU to do an inclined
search). The Antenna Control Unit calculates the Azimuth, Elevation and Polarization values it will
use to target the antenna.
Initially the antenna will go to a calculated position that is half of SWEEP INCR degrees above, and
perpendicular to, the satellite arc (along the same angle as polarization for the desired satellite).
This position is the “Start” of the search pattern in the graphic above. Then the antenna will drive
down along the polarization angle SWEEP INCR degrees, step one Search Increment to the right
(parallel to the 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 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.
2.7.3. No Gyro Search Pattern
If the ship does not have a gyro compass to use as 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 10 or 20 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 – set to the default value for you antenna (refer to SWEEP INC paragraph in
chapter 5 of this manual and FACTORY DEFAULTS in chapter 5 of your antenna manual for
more information).
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,