• NAV-4000 combines ADF and VOR/ILS/MKR receivers in a single package
• NAV-4500 is identical to the NAV-4000 except it does not include the ADF receiver for installations with a single ADF receiver and an option for a dual ADF receiver
• ADF-4000 and VIR-4000 provide these receivers for installations requiring smaller, stand-alone packages
• ARINC 429 and CSDB tuning and data outputs provide a variety of installation options; serial tuning and data output capabilities are identical to those of the ADF-462 and VIR-432
• Single set of high-speed ARINC 429 I/O buses provides tuning, digital audio, navigation data, maintenance data and software data loading capability
• Interfaces with the RIU-4000 allow a concentrated radio interface to the rest of the aircraft
• Reduced size, weight and power set a new standard for business and regional aircraft avionics
• Meets latest DO-160D Change 1 environmental requirements
• Internal diagnostic capability minimizes time spent on fault diagnosis; fault code read out available on CTL or RTU
• Comprehensive maintenance software package works with aircraft maintenance computer and service center test software for improved maintainability

The NAV-4000/4500, ADF-4000 and VIR-4000 are members of the new Pro Line 21 CNS family of products that feature state-of-the-art digital signal processing technology, digital audio, a consolidated tuning/data/audio bus, comprehensive maintenance software and software data loading. The Pro Line 21 CNS products set new standards for size, weight and power in the business and regional aircraft market. They retain the same form factor as the current Pro Line II and Pro Line 4 products (3.3 inches high, 14 inches long) but have reduced widths that allow size reductions of up to 70 percent and weight reductions of up to 55 percent. These products also are designed and tested to meet the more stringent DO-160D Change 1 environmental requirements for helicopters and composite body aircraft.

The NAV-4000/4500, ADF-4000 and VIR-4000 maintain the same serial data and analog audio interfaces as the Pro Line II and Pro Line 4 products, thus allowing them to fit into existing installations with a minimum of modification to the existing aircraft wiring. These legacy interfaces duplicate the operation of the Pro Line II and Pro Line 4 products. For new installations it provides high-speed I/O buses that interface with the RIU allowing use of new features such as software data loading, enhanced maintenance reporting, digital audio, data communications management and data concentration.

The NAV-4000 includes the VOR/localizer, glideslope, marker beacon and ADF receivers in a single package. The NAV-4500 is identical in size and pinout to the NAV-4000 but does not include the ADF receiver. The NAV-4500 is intended for installations offering a single ADF receiver as standard with a dual ADF receiver as an option. The ADF-4000 and VIR-4000 include only the ADF or VOR/localizer, glideslope, marker beacon functionality in packages that are a half-inch smaller in width than the NAV-4000/4500 configuration.

The NAV-4000/4500 is packaged in a 2.5 MCU configuration rather than the 2.0 MCU configuration of the ADF-4000 and VIR-4000. The VIR and ADF receivers in the NAV-4000/4500 share a number of interfaces such as tuning inputs, strapping inputs and power inputs. Some of the VIR and ADF legacy signals that are only required for Pro Line II digital system installations have not been included on the NAV-4000/4500 connector.

The VIR component of the NAV-4000/4500 and the VIR-4000 operates in either the VOR or ILS receiver modes. In the VOR mode the unit utilizes the VHF receiver and outputs VOR bearing at an accuracy of ± 0.2 degrees. In the ILS mode the unit utilizes both the VHF and UHF receivers and provides localizer and glide slope deviation with a centering accuracy of ±0.002 and ±0.009 ddm (difference in depth of modulation) respectively. The marker beacon receiver is operational at all times and outputs logical levels on the data output when positioned above the three marker beacons.

VOR/localizer audio is output as analog audio and also as digital audio to an RIU-4000/4100 on the unit's high-speed ARINC 429 bus. The marker beacon audio has its own analog audio output for stand-alone operation but also provides marker status information to permit tone synthesis when integrated with the RIU.

Extensive self-test and BITE capability allow detection of unit failures and ability to isolate the failure to the subassembly level. Non-volatile memory allows storage of fault conditions as an aid in isolating intermittent failure conditions and to assist in shop-level repair. This information is output on the high-speed ARINC 429 bus along with the navigation information, digital audio and software data loading capability.

The ADF receiver in the NAV-4000 and ADF-4000 determines the location of the radiating signal with respect to the aircraft body and provides this bearing on its digital output bus. The ADF receiver demodulates the AM signal and provides analog and digital audio output to the RIU-4000/4100 on the unit's high-speed ARINC 429 bus. The ADF receiver also provides a BFO function to generate a 1000 Hz audio tone for detection of unmodulated or continuous wave idents.

Extensive self-test and BITE capability allow detection of unit failures and ability to isolate the failure to the subassembly level. Non-volatile memory allows storage of fault conditions as an aid in isolating intermittent failure conditions and to assist in shop level repair. This information is output on the high-speed ARINC 429 bus along with the navigation information, digital audio and software data load capability.