The GTX-327 is Garmin's best Mode C Transponder. It lacks the GTX-330's TIS traffic features, or the ADS-B capability of newer Transponders.  However, it you are using other avionics for ADS-B (or are not subject to this mandate), the GTX-327 is an excellent unit, with many helpful convenience features.

The GTX-327 produces 200 watts of transmission power, offering long range and operation up to 50,000 feet. Plus, the GTX-327 does this without a cavity. As a result, reliability is improved, and no warm-up time is needed before operation.

The GTX-327 features:

• Large, easy-to-read digital display
• Numeric keypad for easy squawk entry
• Dedicated VFR button to squawk 1200
• Count up and count down timers
• Displays pressure altitude from your encoder
• 4096 discrete codes
• Mode C compatibility
• System test capability
• TSO'd

The GTX-320A and GTX-327 are interchangeable. They use the same mounting rack and connector / installation kit. However, the GTX-327 includes additional features (squat switch detection and RS-232 communication) which use connector pins that the GTX-320A does not use. If upgrading from a GTX-320A to a GX-327, a small amount of installation would be needed to utilize these pins for the GTX-327.

The Garmin GTX 327 Transponder is widely installed in single and twin-engine piston and light turbine aircraft, including but not limited to:

• Cessna aircraft – 150, 152, 172, 182, 206, 210, 310, 340, 414, 421, Caravan

• Piper aircraft – Archer, Arrow, Cherokee, Seneca, Navajo, Malibu

• Beechcraft aircraft – Bonanza, Baron, King Air (select models)

• Mooney M20 series

• Diamond DA20, DA40, DA42

⚠️ Note: Compatibility depends on aircraft configuration. Always confirm with your avionics shop or installation documentation before purchase.