Sea Tel 9497B-21, Installation And Operation Manual

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9497B-21 C/Ku-Band TVRO Operation
2-1
2. Operation
2.1. System Power-up
Turn the Power switch on the louvered panel of the antenna pedestal ON. This will energize the antenna pedestal and
the associated RF equipment.
Turn the Power switch on rear panel of the Antenna Control Unit (ACU) ON.
2.2. Antenna Initialization
A functional operation check can be made on the antenna stabilization system by observing its behavior during the 4
phases of initialization.
Turn the pedestal power supply ON. The PCU will initialize the stabilized portion of the mass to be level with the
horizon and at a prescribed Azimuth and Elevation angles. The antenna will go through the specific sequence of steps
(listed below) to initialize the antenna. These phases initialize the level cage, elevation, cross-level and azimuth to
predetermined starting positions.
Initialization is completed in the following phases, each phase must complete properly for the antenna to operate
properly (post-initialization).
1. Level Cage is driven CCW, issuing extra steps to assure that the cage is all the way to the mechanical stop.
Then the Level cage will be driven exactly 45.0 degrees CW.
2. Elevation axis activates - Input from the LV axis of the tilt sensor is used to drive the Elevation of the
equipment frame to bring the tilt sensor LV axis to level (this results in the dish being at an elevation angle of
45.0 degrees).
3. Cross-Level axis activates - Input from the CL axis of the tilt sensor is used to drive Cross-Level of the
equipment frame to bring the cross-level axis of the tilt sensor to level (this results in the tilt of the Cross-
Level Beam being level).
4. Azimuth axis activates - Antenna drives in azimuth until the “Home Flag” signal is produced. This signal is
produced by a Home Switch hitting a cam or by a Hall Effect sensor in close proximity to a Magnet.
This completes the phases of initialization. At this time the antenna elevation should 45.0 degrees and Relative
azimuth should be at be at home flag (home switch engaged on the home flag cam).
If any of theses steps fail, or the Antenna Control Unit reports model number as "xx97" re-configure the PCU as
described in section the Setup section of this manual. If initialization still fails, refer to the troubleshooting section of
this manual.
2.3. Antenna Stabilization
After initialization has completed, real-time stabilization of the antenna is an automatic function of the PCU.
2.4. Stabilized Pedestal Assembly Operation
Operation of the stabilized antenna Pedestal Control Unit (PCU) is accomplished remotely by the Antenna Control Unit
(ACU). Refer to the Operation section of the Antenna Control Unit manual for more specific operation details. There
are no other operating instructions applicable to the pedestal assembly by itself.
2.5. Tracking Operation
Tracking optimizes the antenna pointing, in very fine step increments, to maximize the level of the satellite signal
being received. The mode of tracking used in this antenna is a variation of Conical Scanning called DishScan.
DishScan continuously drives the antenna in a very small circular pattern at 60 RPM. The ACU evaluates the received
signal throughout each rotation to determine where the strongest signal level is (Up, Right, Down or Left) and issues
the appropriate Azimuth and/or Elevation steps to the antenna, as needed.
You cannot control tracking from the pedestal itself. Refer to the ACU manual for tracking operation information.
2.6. Antenna Polarization Operation
Linear feeds are equipped with a polarization motor and potentiometer feedback and are controlled from the Antenna
Control Unit. Auto-Polarization mode is the default polarization mode of operation from the ACU. Polarization may