The IFR Aeroflex NAV401L is an FCC Type-Accepted bench and ramp test set for functional testing and calibration of aviation communication and navigation systems. It generates modulated signals across three frequency bands to support ILS Category I and II certification, marker beacon, VOR, localizer, glide slope, and communication avionics testing. The instrument combines a modulated signal generator, built-in monitoring, frequency counter, and power meter in a single platform.
Technical Specifications
Signal Generation
• Modulated signal generator for MKR, VOR, LOC, G/S, and COMM testing
• Frequency bands: 72–78 MHz, 107–156 MHz, 327–337 MHz
• Crystal frequency tolerance: ±0.005%
• Counter time base accuracy: ±0.002% (0–50°C)
• Phase-locking: 25 kHz intervals (all bands except G/S); 50 kHz intervals (G/S)
• VOR bearing selection: 0.1-degree steps, ±0.1 degree accuracy
• Localizer transmitter output: approximately −18 dBm at generator output jack
Modulation
• Digitally derived tones from 2.16 MHz crystal: 1020 Hz, 400 Hz, 1300 Hz, 3000 Hz (each ±1% accuracy)
• MKR modulation: 95% nominal (±5%), variable 3–96%
• VOR modulation: 30% nominal (±2%), variable 3–55%
• LOC and COMM modulation: 30% nominal (±2%)
Output
• Variable attenuator range: −7 dBm to −110 dBm
• Maximum output: −7 dBm (0.1 V) on any band
Monitoring & Measurement
• VOR bearing monitor (90-degree)
• Modulation monitors: 0–30% and 0–100% ranges
• Power meter: 0–10 W or 0–100 W scales; peak or average selection for COMM transmitter verification
• Frequency counter: Measures RF generator output, COMM transmitter frequency, external signals 1 MHz–300 MHz minimum
– Key Features
• Simultaneous LOC and G/S signal radiation in G/S crystal mode
• Custom frequency selection per band at order time
• Rear panel jack for modulation monitoring and listening
• Crystal and variable frequency modes
– Typical Applications
ILS Category I and II system certification; marker beacon, VOR, localizer, and glide slope receiver testing; communication transceiver power and modulation verification.
– Compatibility & Integration
Designed for direct bench and ramp testing of installed avionics without external ancillary equipment.
