For the most part, the KT-76C is a direct fit and form replacement for the KT-76A. However, there are considerations when replacing a KT-76A that was installed into a 28V aircraft installation. The original KT-76A utilized a voltage changeover (i.e. dropping resistor) kit for the KT-76A to be installed to a 28V installation.  The KT-76C was designed to operate from any input voltage of 11-33 VDC.  Therefore, the dropping resistor is not needed for the KT-76C in a 28V aircraft. The original droppiong resistor is removed from the original KT-76C wiring harness. In addition, the harness fuse needs to be changed from 3A to 5A. If an RFI suppression adapter was installed originally, then it must be removed as well.

A few questions related to the KGX 150 :

1. Can this unit be paired with the KT-76C transponder?
2. What will the Wi-Fi option cost?
3. With our configuration, what antennas will need to be installed to meet the ADSB-Out requirements?
4. Will an additional antenna be required to facilitate ADS-B-In?

There are a few things to be aware of with all UAT installations. These units require a control device and a switch to place them in air/ground mode. The switch is not a major issue and is a minor cost. However, the controller is additional if the aircraft is not already equipped with a transponder and/or display (MX20 for example).

As you’ll see below, yes, the KT-76C will pair with the unit via the antennas. Basically the UAT will sense the XPDR. This will enable you to send the Mode A and IDENT information to the UAT unit. However, you are still required per the FAA to have a way to know your ADS-B status. If a suitable display such as the Garmin MX20, Aspen EFD1000 or the KSN 770 is not installed, then a remote control unit is required. The KGX Control Panel list price is currently $619. Depending on the aircraft and the kind of flying, there are a lot of factors and options to consider.

1. Can this unit be paired with the KT-76C transponder?
   • Yes
2. What will the Wi-Fi option cost?
   • The Wi-Fi option will run around $349 list for parts.
3. With our configuration, what antennas will need to be installed to meet the ADS-B-Out requirements?
   • Per the STC, you will be required one external WAAS/GPS antenna and at least one UAT antenna.
4. Will an additional antenna be required to facilitate ADS-B-In?
   • No, as long as the unit purchased is the transceiver. However, you will need a suitable display for the "In" without the Wi-Fi.

A Guide to Panel Mount Transponders

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 shop@seaerospace.com.

The VFR code can be programmed from the front panel of the KT-76C. Please follow these steps:

1. Select SBY (Standby) on the control knob
2. Enter the desired VFR code with ident code pushbuttons (0-7)
3. Press the "VFR" button while holding in the "IDT" button
Note: Pressing and holding the "VFR" button for 2 seconds will retrieve the last non-VFR 4096 code

Negotiating the exchange price of a unit only limits the allowable repair cap for the core unit. Southeast Aerospace's exchange transactions are based on the return of economically repairable core unit. Once the core is received and evaluated, the core repair cost incurred by SEA cannot exceed 75% of the original exchange price. That is, it cannot cost SEA more than 75% of the original OH/SV exchange price collected from the customer. Therefore, when and if an SEA exchange price is discounted, there is a risk that additional charges may be assessed once the core is returned and evaluated.

For more information, please refer to these other Exchange FAQs

Although some manufacturers call out specific transponder antennas in their installation manuals, almost any transponder antenna can be used with any transponder. Various models are available based on the screw hole pattern desired and the speed & drag considerations based on the aircraft type.
 

 

 

 

Ultimately, it is the responsibility of the installer or installing agency to determine what antenna is suitable for the aircraft application.

 

 

 

Much of the KT-76C unit includes circuit boards assembled with surface mounted components or SMCs. By nature, surface mount devices or SMDs contain much smaller components with tighter placement on both sides of the board. Compared to circuit board assemblies with traditional through-hole mounting, SMDs can be much more difficult to repair on the component level given to small size and lead spacing of the SMCs.

The original KT-76A mounting rack Part Number is 047-03898-0002. The rack included with a new KT-76C is Part Number 047-09628-0004. Either unit will fit into either rack. Also, as a direct, slide-in replacement for the KT-76A, the KT-76C utilizes the same connector in the same rack position as the KT-76A.

Rack P/N 047-09628-0004 was also used with the KT-70 and KT-71 transponders. Therefore, the 047-09628-0004 rack included additional features such as a port for cooling fan connection and space for a configuration module.