ACK A-30.9 Altitude Encoder Overview:

A-30.9 Altitude Encoder with Dual RS-232 Outputs

The A-30.9 altitude encoder is a compact, high-accuracy solution designed to work with modern Mode A/C and Mode S transponders. It provides both parallel gray code and dual RS-232 outputs, allowing flexible integration with a wide range of avionics systems.

The mod 9 configuration reports altitude up to 42,000 feet and supports RS-232 output in either 10-foot or 100-foot increments. Output formats are jumper selectable, making it adaptable to different installation requirements. It is also plug compatible with earlier mod 1 through 4 and mod 8 encoders with serial numbers 2,400 through 120,499.

This encoder kit includes a quick-release mounting tray, a four-foot color-coded harness with prewired jack, static line fittings, and an installation manual for straightforward installation.

• Dual RS-232 outputs with selectable formats
• RS-232 altitude reporting selectable in 10-foot or 100-foot increments
• Parallel gray code output
• Altitude reporting up to 42,000 feet (mod 9)
• Plug compatible with earlier A-30 encoders (mod 1 through 4 and mod 8, serial numbers 2,400 to 120,499)
• Includes mounting tray, wiring harness, static fittings, and installation manual

Technical Specifications

• Weight: 5.1 oz (144 grams)
• Dimensions: 6 x 2.65 x 1.3 inches
• Range: -950 to 42,000 ft (mod 9)
• Accuracy: ±20 ft typical, ±50 ft maximum
• Altitude Resolution: RS-232 selectable 10 ft or 100 ft, gray code output 100 ft
• Operating Voltage: 10 to 32 VDC
• Operating Current: 160 mA typical
• Warm-up Current Draw: 14 VDC at 160 mA, 28 VDC at 220 mA
• Warm-up Time: 60 seconds at 70°F, 210 seconds at 0°F
• Operating Temperature: -4°F to 131°F (-20°C to 55°C)
• Approvals: FAA TSO C-88a, German LBA 10.221/4