I'm pretty sure the Trig transponder allows the GND/ALT determination to
be made without use of a squat switch.

On 11/30/2019 1:21 PM, Charles Longley wrote:
Actually out of curiosity I looked at the pin out diagram for a Garmin transponder. There’s no pin out for a squat switch. Guess they do air-ground logic through programming as quoted by AOPA. Too bad they don’t make a smaller transponder.

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Dan, 5J