The Marconi IFR Aeroflex MLS-801 is a portable ramp test set for verification and calibration of Microwave Landing System (MLS) angle receivers in aircraft. It generates single-channel MLS signals with AM and DPSK modulation to validate airborne receiver functionality and accuracy during maintenance and troubleshooting operations. The instrument provides GO/NOGO verification across azimuth, elevation, back azimuth, and clearance functions while supporting dynamic angle control, multi-path simulation, and automated test sequences.
Technical Specifications
Signal Generation & Modulation
• Single-channel signal with AM and DPSK modulation
• Azimuth (AZ), elevation (EL), back azimuth (BAZ), and clearance (CLR) functions
• Complete MLS transmission cycle simulation with all angular information and data words
• Basic and auxiliary data word simulation with parity selection
Angle Control
• Azimuth offset: ±40 degrees
• Elevation angle: 1 to 10 degrees
• Dynamic slew rates: 0.05, 0.1, 0.5, and 1.0 degrees per second
• Manual azimuth and elevation deflection
• Control motion deflection for auto-pilot coupling tests
• Left and right clearance pulse simulation
RF Performance
• Fixed transmission frequency: 5031 MHz ±10 kHz (FAA channel 500)
• High range RF level: -69.5 dBW/m² @ 30 ft
• Low range RF level: -89.5 dBW/m² @ 30 ft
• Beam level: 6 dB above preamble (±2 dB accuracy)
Multi-Path Simulation
• Interference pulse simulation
• Selectable fade rate modulation: 0.05, 1, and 1000 Hz
Power
• Internal battery: approximately 2 hours operation
• AC input for charging or continuous operation
• 80% charge time (unit off): approximately 2 hours
• Automatic shutdown: 15 minutes non-use
Environmental
• Operating temperature: -40°C to +55°C
• Storage temperature: -40°C to +71°C
• Rugged construction per MIL-T-2880
– Key Features
• Automatic test sequence for single-operator use
• Built-in-test (BIT) for confidence testing and fault isolation
• Auxiliary RF, video, and sync pulse outputs for bench testing
– Typical Applications
• Aircraft MLS receiver verification and calibration
• Ramp and tarmac maintenance operations
• Navigation system troubleshooting
– Compatibility & Integration
Designed for direct testing of airborne MLS angle receivers without modification to aircraft systems.
