Part #: 066-01164-0101

Model: KT-73






Mode S Transponder, Digital Datalink

Part Number :




  • Silver Crown Plus digital panel mounted Transponder with Mode S Level 2 Datalink
  • Currently (08/2012) the KT-73 does not meet DO-260B which is indicated as an ADS-B mandate
  • Not TCAS compatible
  • Designed for light aircraft
  • Offers comprehensive functional and safety capability for piston aircraft operators which includes data linked traffic information services to the cockpit
  • Unique address code allows improved aircraft surveillance and reporting accuracy
  • Ability to enter and display 8 digit alpha-numeric Flight ID code (i.e. a/c ID employed in flight plan)
  • Reduced interference in identity and altitude reporting
  • Capable of exchanging Surveillance and Comm-A interoggation to ADLP (Airborne Data Link Processor) for enhanced Mode S applications
  • Easy-to-read gas-discharge display with encoded altitude and assigned code information
  • 4 knobs for code selection
  • Pushbutton VFR code selection
  • Built-In Test Equipment (BITE) provides continuous self-test capability
  • Backlighted bezel nomenclature and knobs for recognition during night flights
  • Features air/ground discrete that can disable ATCRBS and Mode S all-call replies when aircraft is on ground
  • TSO'd as Class 3A transponder suitable for operation up to 50000 feet
  • Meets TSO-C112 for Class 2A ATCRBS Mode A and C/Mode S Airborne Transponder Systems
  • Meets European classic surveillance mandate and JTSO-2C112a
  • Capable of interfacing to KMD-550 or KMD-850 Multi-Function Displays (with KAC-504 traffic module) for displaying traffic information available from FAA secondary surveillance radars
  • Capable of interfacing to KMD-250 Multi-Function Display for displaying traffic information (additional module not required)
  • Capable of interfacing to KI-825 Electronic HSI for displaying traffic information (forthcoming as of April 2004)
  • Fits same mounting rack as KT-76C,KT-70, and KT-71 transponders
(Note: Mounting rack must be changed in retrofit to new style KT-73 rack if TIS, ADLP, or ADS-B features are going to be utilized via second auxiliary connector on KT-73) (Note: Mounting rack must be changed in retrofit to new style KT-73 rack if installation is in rotary aircraft)
  • Optional configuration module available to sotre address with the rack allowing units to be swapped from rack to rack eliminating the need to reprogram the aircraft address or other configuration parameters
(Note: Installing the configuration module is the only way to access signals from the auxiliary connector - e.g. audio output for traffic, RS-232 transmit) Click Here to view a basic interconnect diagram for the KT-73 (note: reference only) Click Here to view traffic displayed on the KMD-550/850 Click Here to view traffic displayed on the KMD-250 Click Here to view the KT-73 Pilots Guide




Size: 6.25"W x 1.63"H x 10.82"L Weight: 3.63 lbs.
TSO: C112, DO-181B, DO-178B, DO-160D Temperature: -20 to +55C
Altitude: 50000 feet Display: Digital, Gas Discharged
Max. Current Draw: 2.5 amperes Output Power: 200 watts
Type: Mode S Level 2 Datalink Voltage: 10-32VDC
Compliance: ED-73 and ICAO Manual on Mode S Specific Services Cooling: Optional
Part Number: Description:
066-01164-0101 Mode S Transponder, Digital Datalink


- Mode S Transponder

NSN: 5895-01-530-4575

Price Condition Status

Click on a question below to see the answer. If you have a question about this model that is not answered below, please contact

No. The Bendix/King KT-73 Level 2 Datalink Transponder uses a different mounting rack and installation kit from the KT-76A. However, the KT-73 does use the same mounting rack as the KT-76C.
No. The KT-73 Level 3 Datalink transponder will only be used for terminal areas not enroute air traffic control. Congested terminal areas poses the greatest challenge for ATC maintaining safe separation and tracking of aircraft.
The KAC-504 traffic module must be installed into the KMD-540 MFD unit (P/N 066-04035-XX0X) to display the traffic information from the KT-73 TIS/Mode S transponder. It should be noted that the Traffic Information Service (TIS) is currently only available in certain areas of the United States.
Many avionics systems require a configuration or setup process. This process is required to interface certain avionics systems to other systems in the aircraft that will be inputting or outputting information to and from these systems. Some examples of systems that require a configuration or setup process include:


In addition, most newer technology or solid state systems require configuration via computer interface of some type. A qualified avionics technician should always refer to the appropriate manufacturer's installation manual for complete information and instructions.
Yes, anytime a transponder is removed or replaced an altitude correlation between what the transponder is reporting and what is displayed on the altimeter needs to be performed. This is outlined in FAA CFR Part 91.413. This regulation indicates that following any installation or maintenance of a transponder where data correspondence error could be introduced, the integrated system has been tested, inspected, and found to comply with paragraph (c), appendix E. Furthermore, these references indicate that an integration test between the altitude reporting equipment and transponder system must be conducted.

For complete information, please refer to these FAA regulations or contact Southeast Aerospace Tech Support team at
The KT-73 will fit into most of KT-70/71/76A/76C mounting racks and utilizes the same main connector. However, there are other factors to consider. First, the KT-73 rack includes a configuration module that will store aircraft parameters for the Mode S function. This configuration module is located in the silver box on the right side of the rack (please see photo). In addition, the configuration module has a male connector which can be seen when you peel off the silver tape from the box (see second photo). The designation of this connector is JKT73-4.

All of the TIS (traffic) interface connections for the KMD-550/850 interface are not located on the main connector of the KT-73 (JKT73-1). The TIS ARINC 429 data is output from the KT-73 into the KMD-540 MFD and then output from the KMD-540 into the small config module connector. The small mating connector for JKT73-4 can be purchased separately however it is more cost effective to simply purchase the entire KT-73 installation kit for this scenario.

In conclusion, when upgrading the KT-70/71/76A/76C transponder to the KT-73 with the intention of interfacing to the KMD-550/850 MFD for TIS traffic, you must purchase the correct KT-73 mounting rack and installation kit.
The Mode S aircraft identification code is listed on AC Form 8050-3, Certificate of Aircraft Registration, as the International Civil Aviation Organization (ICAO) Aircraft Address Code. If the aircraft registration does not contain this information, aircraft owners with a Mode S transponder can obtain an aircraft identification code from the FAA Aircraft Registry in Oklahoma City, Oklahoma. This may be accomplished by writing to the following FAA address:

Federal Aviation Administration
Aircraft Registration Branch AFS-750
P.O. Box 25504
Oklahoma City, OK 73125-0504

You may also call:
No, the KT-73 does not meet ADS-B requirements. Previously, the KT-73 could be interfaced to the KMD-540 MFD for display of TIS traffic when operating an aircraft in area with TIS coverage. As of 2013, Bendix/King is working on a replacement for the KT-73 that will comply with the ADS-B mandate.
No, the KT-73 does not and will not meet any ADS-B requirements. There is no upgrade path from the KT-73 other than replacing the KT-73 with an ADS-B capable transponder such as the KT-74 or competing OEM product.

In relation to NE (New) parts, many OEMs change their prices and availability without any notice to dealers or the industry. Therefore, through the REQUEST or RFQ indication, we ask that customers contact us for the most accurate price and availability.

In relation to SV & OH parts, the used parts aftermarket in the aviation industry is not an infinite supply. It is a dynamic, constantly changing market that is significantly affected by and susceptible to highs and lows in supply and demand. Therefore, although we attempt to, at times, we are unable to predict the exact moment when an item may be available. Once again, through the REQUEST or RFQ indication on our website, we ask that customers contact us for the most current and accurate price and availability.

PLEASE NOTE - Publications are for Reference Only