The Marconi IFR Aeroflex NAV750B Bench Test Set is a self-contained simulator for semi-automatic functional testing and calibration of airborne navigation and communication receivers. It generates VOR, Localizer, Glide Slope, Marker Beacon, and COMM signals to evaluate receiver performance without additional test equipment.
Technical Specifications
Signal Generation & Frequency Coverage
• VOR: 108 MHz to 117.95 MHz
• ILS/Glide Slope: 329.15 MHz to 335 MHz
• NAV/ILS: 108 to 156 MHz in 25 kHz increments
• Glide Slope: 329 to 335 MHz
Output Power Levels
• VOR: 0.1 μV to 1000 μV
• ILS: 0.1 μV to 300 μV
• RF Power: ±1.5 dB to -50 dBm; ±2.5 dB from -50 dBm to -120 dBm
• RF Output Range (NAV-750BR): -127 dBm to 0 dBm in 1.0 dB steps
Modulation Capabilities
• VOR: 30 Hz, 9960 Hz, or combined 30 Hz + 9960 Hz
• ILS/Glide Slope: 400 Hz, 1300 Hz, 3000 Hz, 9960 Hz
• COMM: 1020 Hz
• AM Depth: 0 to 99.9% with 0.1% resolution; <3% distortion at 1 kHz for depths to 80%
• FM Deviation: <3% distortion at 1 kHz for deviations to 100 kHz
Frequency Accuracy & Stability
• Frequency accuracy: ±10 ppm; ±50 kHz (108–156 MHz); ±150 kHz (329–335 MHz)
• Internal TCXO: Better than ±1 ppm (15–35°C); ±3 ppm (10–45°C); <±2 ppm/year aging
Phase & Bearing Control
• LOC and VOR Tones: Phase-locked to ±0.1° or continuously variable
• VOR Bearing: Twelve 30° presets plus ±10° steps and 0.01° or 0.05° continuous adjustment
• Bearing Accuracy: ±0.05°; independent counter displays to 0.01° resolution
• LOC Deviation: ±0.046 DDM, ±0.093 DDM, ±0.155 DDM, continuously adjustable ±0.4 DDM
Spectral Performance
• Harmonics: Typically 3 kHz offsets): <-70 dBc to 1 GHz
• Close-in phase noise: -74 dB below carrier at ±20 kHz
Frequency Selection
• ARINC Two-Out-of-Five Wire output with 25 kHz spacing and automatic channeling
• 40 paired LOC-Glide Slope frequencies with automatic VOR or LOC modulation selection
– Key Features
• Semi-automatic test and calibration operation
• Preset and continuously variable signal parameters
• Independent bearing monitor with 0.01° resolution
• Supports full ILS and VOR test sequences
– Typical Applications
• Avionics maintenance facility calibration and functional testing
• VOR, Localizer, Glide Slope receiver validation
• Marker Beacon and COMM system verification
• Compliance validation of airborne navigation equipment
