What is the difference between the TT21 and the TT22?
Both models have the same physical dimensions and advantages of size and ease of installation. The TT21 is a 130 watt Class 2 transponder; this makes it ideal for light sports and regular GA use. The TT22 is a 250 watt Class 1 transponder, ideally suited to higher performance and/or high altitude performance types.
In the U.S. the FAA has stated that Class 1 transponders must be used to be ‘2020 complaint’ For U.S. customers Trig recommends the TT22 unit for this reason.
Is the controller display visible in all lighting conditions?
Yes! The LCD display is clear and crisp in all lighting, full sunlight generates a very clear contrast and in dull or dark lighting the inbuilt lighting ensures the unit remains clear and legible. The controller has a backlight and manual dimming can be selected to increase or decrease brightness.
Is the controller easy to use?
Yes! One handed operation is simple. The Squawk code is easily entered using fingers to rotate the ‘CODE’ dial whilst the thumb is used to press the ‘ENT’ key. All operations can be performed whilst wearing flying gloves.
How does the compact fit or the round mount installation work?
The transponder control head, the TC20 can be installed either as a space saving compact mount or in a 57 mm round hole. Click on the 'specification tab' of this web page to see an image of the installation kit, in the technical images area. This photo features all the components contained in the install kit. This includes the two plastic blanking plates and long screws that are used to fit the TC20 control head into a 57 mm round hole. Once installed, the full round mount is a tough and durable solution, it looks great in both modern and vintage aircraft. The kit also includes a template to assist you in cutting an accurate compact mount in the panel, if that is required.
Can I use the Transponder in open cockpit flying?
The TC20 controller is splash proof. This makes it suitable for use in open cockpit aircraft, where the weather can sometimes be in the cockpit and not just outside it!
In Europe, how do I get a free minor change?
Free minor changes for the TT21 and TT22 are available, see our minor change library. You may also consider the alternative EASA approval called CS-STAN this is especially suited to VFR aircraft.
Does the TT22 have an STC?
Yes, Trig has a free STC with an AML list of over 576 types.
In the U.S. installing a compliant ADS-B Out solution (in a certified aircraft) requires your Trig transponder to utilise a certified WAAS GPS, this provides a compliant ADS-B position source. The FAA also requires that a certified ADS-B installation is completed in accordance with an FAA STC approval (Supplementary Type Certificate).
Our ADS-B STC’s are available free of charge and cover hundreds of aircraft types. Trig STC approvals allow the use of popular WAAS GPS navigators too – making installation more practical and cost-effective. Our TA70 GPS antenna has also been added to our STC equipment list.
