Sea Tel ST88-21 C/Ku-Band TVRO, Installation And Operation Manual

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ST88-21 Technical Specifications ST88-21 C/Ku-Band TVRO
14-2
14.3. Stabilized Antenna Pedestal Assembly
Type: Three-axis (Level, Cross Level and Azimuth)
Stabilization: Torque Mode Servo
Stab Accuracy: 0.3 degrees MAX, 0.15 degrees RMS in presence of specified ship
motions (see below).
LV & CL motors: Size 34 Brushless DC Servo motor with integrated brake.
AZ motor: Size 34 Brushless DC Servo motor with integrated encoder .
Inertial Reference: Solid State Rate Sensors
Gravity Reference: Two Axis Fluid Tilt Sensor
AZ transducer: 256 line optical encoder (integrated in AZ motor) / home switch
Range of Motion:
Elevation -15 to +110 degrees
Cross Level +/- 25 degrees
Azimuth Unlimited
Polarization +/- 90 degrees
Elevation Pointing: 0 to +90 degrees (with 15 degree Roll)
+5 to +90 degrees (with 20 degree Roll)
+10 to +85 degrees (with 25 degree Roll)
Relative Azimuth Pointing Unlimited
Specified Ship Motions (for stabilization accuracy tests):
Roll: +/-15 degrees at 8-12 sec periods
Pitch: +/-10 degrees at 6-12 sec periods
Yaw: +/-8 degrees at 15 to 20 sec periods
Turning rate: Up to 12 deg/sec and 15 deg/sec/sec
Headway: Up to 50 knots
Mounting height: Up to 150 feet.
Heave 0.5G
Surge 0.2G
Sway 0.2G
Maximum ship motion:
Roll +/- 25 degrees (Roll only)
+/- 20 degrees (combined with Pitch)
Pitch +/- 15 degrees
Yaw Rate 12 deg/sec, 15 deg/sec/sec