Garmin GTX™ 325 - 010-01083-01
The Garmin GTX™ 325 is a Mode C transponder for aircraft panel installations, combining a digital display with 14/28 VDC operation. Its compact 1.68” x 6.30” x 10.07” (42 x 160 x 256 mm) form factor makes it a practical consideration where panel space and transponder capability are key priorities.
Compact Panel Footprint
Preserve valuable panel space with a compact transponder package. Dimensions for the unit, rack, and connectors are 1.68” x 6.30” x 10.07” (42 x 160 x 256 mm), with depth measured from the face of the instrument panel.
High-Altitude Operating Range
Support operations at substantial altitudes with an operating altitude rating to 55,000 ft (16,800 m). The specified operating temperature range is -40° C to +70° C.
No Cooling Input
Simplify cooling provisions with no cooling input required. The GTX™ 325 operates on 14/28 VDC and is specified at 14 W maximum.
Digital Transponder Operation
The GTX™ 325 uses a digital display and provides 200 W minimum transmit power. At 2.9 lbs (1.32 kg), the stated weight includes the unit, rack, and connectors. These defined electrical and physical characteristics help support informed panel-planning decisions.
Environmental And Software Standards
The GTX™ 325 is TSO Approved for DO-160G environmental compliance. Its TSO Approved software compliance is listed as DO-178 Levels B, C, D. These specifications document the standards identified for this Mode C transponder configuration.
Not sure this is the right fit for your aircraft?
Avionics compatibility can vary based on your aircraft, existing equipment, and planned installation. Give Neal Avionics a call or send us an email—we’ll be happy to help you review the product and determine whether it fits your needs.
Digital Mode C Transponder Solution
- Modern, digital Mode C transponder perfect for aircraft that fly in airspace where ADS-B isn’t required or on aircraft that is equipped with a UAT ADS-B solution
- Offers useful timing and display functions such as timers, altitude monitoring, current pressure altitude readout and more
- Easy replacement for existing transponders, with common 1.65” tall form factor
- Optional Garmin altitude encoder simplifies installation, saves space and reduces potential service expenses should the transponder need to be removed
- Connects to GTN™ series navigators for transponder code selection and control
Offering a simple, affordable replacement for standard Mode C transponder units in aircraft that don’t fly in ADS-B mandated airspace — or that will be equipped with a separate UAT ADS-B transceiver solution — the GTX 325 transponder is a reliable, TSO-certified problem solver. Its solid-state design works to maximize service life and assure dependable ATC traffic surveillance.
A Smarter Way to Squawk
Featuring an easy-to-read LCD display designed for optimal viewing in all lighting conditions, GTX 325 offers a number of useful timing and display functions. Timers include trip time, flight time, count-up and count-down, while display functions include readouts for density and pressure altitude as well as static (outside) air temperature. In addition, the altitude monitor function displays the current deviation from the chosen altitude, as well as provides a “leaving altitude” alert when the deviation exceeds the preset limit. Dedicated push buttons numbered 0 through 9 make for quick and easy squawk code entry, while a dedicated VFR button pulls up the VFR code with a single keystroke. Compatibility with the GTN 750 and GTN 650 series of integrated GPS/Nav/Comm systems also enables transponder code selection and control from your navigator’s touchscreen display.
Altitude Encoding Made Simple
The GTX 325 transponder can also be paired with an optional Garmin altitude encoder to satisfy Mode C data transmission requirements for IFR. The external Garmin altitude encoder mounts separately on the install rack. So, if the transponder ever requires removal, there’s no need for the static line to be disconnected. In turn, that eliminates the need for a follow-on leak check — and thus helps minimize ongoing service costs.
Keeps Your Stack Intact
No matter how your aircraft is currently equipped, our GTX 325 offers a simple, all-bases-covered transponder upgrade solution. The standard size and form factor of the 1.65” high unit assures a straightforward replacement for most existing stack-mount transponders — preventing extra avionics rework and installation downtime. See your authorized Garmin installation center for more details on the GTX 325 upgrade for your aircraft.
Remote Mount
Remote mount versions require a compatible display to control transponder modes and squawk code entry.
Integrated GPS
For aircraft without a compatible ADS-B positon source, select versions are available with an integrated WAAS GPS.
Diversity
Diversity versions use two antennas — mounted on the top and bottom of the aircraft — to provide superior operational coverage
Specifications, Compatibility & Documentation
Review detailed technical specifications, compatible avionics interfaces and available product documentation for the Garmin GTX™ 325 - 010-01083-01. This information can help aircraft owners and operators understand the product’s physical requirements, supported equipment and installation considerations.
Specifications and compatibility information are provided for general reference and may change without notice. Final aircraft eligibility, approved configuration, equipment compatibility and installation requirements must be confirmed by Neal Avionics before installation.