ARINC 708A : 1999

1.0 INTRODUCTION
1.1 Purpose of this Equipment
1.2 Purpose and Limitations to this Characteristic
1.3 System Description
1.4 Interchangeability
1.5 Regulatory Approval
1.6 Reliability
1.7 Reference Documents
2.0 INTERCHANGEABILITY STANDARDS
2.1 General
2.2 Form Factors, Connectors and Index Pin Coding
2.3 Interwiring
2.4 Power Circuitry
2.5 Weights
2.6 Environmental Conditions
2.7 Cooling-General
2.8 Input Signal Characteristics
2.9 Audio Outputs
2.10 Radome
2.11 RF Transmission Line
2.12 Antenna Gain Compensation
2.13 Grounding and Bonding
3.0 SYSTEM DESIGN AND PERFORMANCE REQUIREMENTS
3.1 Performance
3.2 Display Characteristics
3.3 Controls
3.4 Radio Frequency
3.5 C-Band System
3.6 Operating Conditions
3.7 Dual Operation
3.8 Sensitivity Time Control (STC)
3.9 Turbulence Detection
3.10 Anti-Clutter
3.11 Alert Outputs
3.12 LRU Failure Indicator
3.13 Master/Slave Operation (Optional)
4.0 TRANSMITTER-RECEIVER UNIT DESIGN
4.1 General
4.2 Automatic Gain Control (AGC)
4.3 STC
4.4 Range Resolution
4.5 Dynamic Range
4.6 Antenna Stabilization
4.7 Digital Inputs for Windshear Detection
4.8 Serial Digital Control Inputs
4.9 Serial Digital Data Outputs
4.10 Test Facilities
4.11 Service Adjustments
4.12 Cooling
4.13 Waveguide Window
5.0 ANTENNA UNIT DESIGN
5.1 Design Criteria
5.2 Scan Angle and Rate
5.3 Tilt
5.4 Stabilization
5.5 Beam Width and Shape
5.6 Mounting
5.7 Antenna Gain Compensation
6.0 CONTROL DISPLAY UNIT (CDU)
6.1 General Design Criteria
6.2 Controls
6.3 Screen
6.4 Focusing
6.5 Resolution
6.6 Panel Lighting
6.7 Shielding
6.8 Control Data Bus
6.9 Display Data Bus
6.10 Auxiliary Data Bus
6.11 TCAS Interface (Optional)
6.12 System Performance Annunciator
6.13 Cooling
6.14 Auxiliary Data Display Functions (Optional)
6.15 Caution and Mode Indicators (Optional)
7.0 SEPARATE DISPLAY UNIT (DU) DESIGN
7.1 General
7.2 Controls
7.3 Display Data Bus
7.4 Cooling
7.5 Auxiliary Data Bus (Optional)
7.6 TCAS Interface (Optional)
8.0 CONTROL PANEL DESIGN
8.1 General
8.2 Controls
8.3 Control Data Bus
8.4 Windshear Auto Turn-On Inhibit
9.0 RADOME DESIGN
9.1 General
9.2 Transmission Efficiency
9.3 Reflection
9.4 Side Lobe Levels
9.5 Anti-Icing
9.6 Beam Deflection Errors
9.7 Beam Width
10.0 PROVISIONS FOR TEST
10.1 Built-In Test Equipment
10.2 Fault Reporting Protocol
10.3 Automatic Test Equipment
ATTACHMENTS
1 Notes Applicable to Standard Interwiring
2-1 Single System Standard Interwiring
     (Single or Dual Displays)
2-2 Dual System Standard Interwiring
     (Single or Dual Displays)
3 Transmitter/Receiver Connector Layout
4-1 Transmitter/Receiver Form Factor (X-Band)
     T/R Unit
4-2 Transmitter/Receiver Form Factor (C-Band)
     T/R Unit
4-3 Waveguide Connection T/R Unit (X-Band)
4-4 Waveguide Connection Rack Unit (X-Band)
4-5 Dual Installation (X-Band)
5 Control/Display and Display Connector Layout
6-1 Display Form Factor
6-2 Display Mount
7-1 Control Panel Connector Layout
7-2 Control Panel Form Factor (Per MS25212)
8-1 Standard Aircraft Mounting Provisions for Antenna
8-2 Antenna Space Provisions (Maximum Swept Volume)
8-3 Analysis of Antenna Mounting Roll Tolerance
9-1 Antenna Connector Layout
10-1 Antenna Form Factor (X-Band Line of Sight)
10-2 Antenna Form Factor (C-Band Line of Sight)
11-1 Installation Configuration 0, 2 and 4
     (Single T-R)
11-2 Installation Configurations 1, 2 and 5
     (Single T-R Dual-Display)
11-3 Installation Configuration 6 (Single T-R-Triple
     Display)
11-4 Installation Configurations 0, 2 and 4 (Dual T-R)
11-5 Installation Configurations 1, 2 and 5 (Dual T-R
     Dual-Display)
11-6 Installation Configuration 6 (Dual T-R Triple
     Displays)
11-7 Control Bus Usage
11-8 Data Bus Usage
12 Performance Index Curves (Weather Only)
13 Radar Stabilization Tolerances Summary
14 Environmental Test Categories
15-1 Weather Radar Serial Control Data Control Word 1
15-2 Weather Radar Display Data Bus Format
15-3 Hazard Data Bus Format
15-4 Windshear Discrete Input Word
15-5 Typical Fault Summary Word
15-6 Fault Messages for WXR Bite (Label 356)
16 Installation Configuration Programming
17 Display Data Bus Termination
18 Auxiliary Data Bus Interface
19 International Standards Organization Code #5
20 Waveguide Switch Electrical Interface
21 ARINC 429 Input for Terrain Based Automatic Tilt
APPENdICES
A Physical, Electrical, and Signal Characteristics
     of Display Data Bus
A-1 Timing Characteristics
B Non-Standard Applications

This Characteristic describes an airborne pulse Doppler Weather Radar system intended for installation in commercial transport type aircraft.