LUN1795.2 is designed to display the horizontal situation (HSI). Data are received via ARINC 429, RS-422 data buses, and analog inputs for selsyn/resolver/discrete signals. The processed data are displayed on the device’s square color display.
The unit supports multiple HSI display modes, allowing adaptation to different operational or regional practices. The display resolution is 1200 × 1200 pixels and supports NVIS compatibility.
Technical Parameters
RS 232: 1× Service port
ARINC 429 RX: 4× Input port
GPIO: 4× Digital input or 2× Relay output
AN IN: 1× Analog input
ARINC 407/Russian: 3× Synchro/Resolver
Inputs: 1× Vertical and lateral deviation
RS 232/422 (optional): 2× Input port
ARINC 429 TX (optional): 2× Output port
MIL 1553 (optional): 2× Bus
DIN (optional): 2× Digital input
XYZ/SinCos (optional): HDG, ROLL, PITCH, ADF/RMI/VOR (SinCos/Synchro)
CDI: NAV/Annunciators, ToFrom, Flags
General Parameters
Voltage (nom.): 27,5 V DC
Voltage (operative): 11…30 V DC
Current (nom.): 0,3 A
Power Consumption: 10,25 W
Operating temperature: -55 – 70 °C
Storage temperature: -55 – 85 °C
Humidity: max. 95 %
Connectors: Circular 37 pin
Dimensions: 132 × 123 × 123 mm
Weight: 1300 g ± 10 %
Display Parameters
Display area: 94,5 (H) × 94,5 (V)
Number of dots: 1200 (H) × 1200 (V)
Number of color: 10bit/color (1,07 B)
Luminance: 1200 cd/m2
Viewing angle: >-80~80° (H), -70~80° (V)
Back-light unit: Edge-light, LED, optional NVIS-B
The device is an electronic unit with a 5-inch HSI display. It consists of three printed circuit board (PCB) modules:
- Communication module (ARINC 429, RS-232/422, GPIO, power supplies)
- Analog module (XYZ / SinCos / discrete inputs)
- Control module (NXP processor with safety FPGA)
The PCBs are detachable, interconnected via precision connectors, and mechanically secured.
The following certification levels apply to this product:
- Environmental Certification Level: RTCA/DO-160E
- Software Level: RTCA/DO-178B Level C
Supported Inputs
The display supports analog inputs such as synchro (XYZ), resolver (Sin/Cos), CDI/VDI deviations, TO/FROM signals, and other analog signals connected to the ADC.
It also supports up to four ARINC 429 input channels for devices such as the Garmin GTN 6xx or 7xx series. Additional devices communicating via digital buses (e.g., DME) can also be connected.
Heading
- Model Description: Gyrocompass system
- Signal Type: XYZ, Sin/Cos, ARINC 429
- Description: Magnetic heading of the aircraft/helicopter
VOR
- Model Description: NAV receiver
- Signal Type: XYZ, Sin/Cos, ARINC 429
- Description: Omni-bearing to VOR beacon
ILS
- Model Description: GS/LOC receiver
- Signal Type: CDI, VDI, ARINC 429
- Description: Lateral and vertical deviation from ILS transmitters
ADF
- Model Description: ADF receiver
- Signal Type: XYZ, Sin/Cos, ARINC 429
- Description: Relative bearing
GPS
- Model Description: GTN 750Xi / 650Xi / 635Xi / 625Xi
- Signal Type: ARINC 429
- Description: GPS source providing waypoints, flight plan, speed, and estimated time to destination
Other Inputs
- ILS Energize
Determines whether the NAV is tuned to ILS and transmitting LOC and GS deviation signals - Weight on Wheels / Ground Mode
Detects whether the aircraft is on the ground; when active, enables access to the service menu - NVIS Switch
Enables external control of NVIS-compatible backlighting - External Light Sensor
Allows external control of display and button brightness - Marker Beacons
Three discrete inputs for approach and landing beacons - DME
Receives distance information via ARINC 568 or ARINC 429
Interfaces
Interfaces are configurable and may vary depending on the application:
- ARINC 429 RX: 8× input ports
- ARINC 429 TX: 3× output ports
- RS-232/422/485: 3× communication ports
- RS-232: 1× service port
- Digital Outputs (Solid State): 6×
- Digital Inputs: 8×
- DME (ARINC 568) receiver
- Marker beacon receiver
- Selsyn/Resolver: 3× inputs
- CDI channel: 1× (Left/Right, Up/Down, TO/FROM)
- MIL-STD-1553 (optional): 2× buses
- ARINC 825 (CAN bus, optional): 1×
