Radiomaster GX15 MAX – configurable ExpressLRS radio for precise model control

Radiomaster GX15 MAX brings together aluminium AG02 gimbals, a top-mounted touchscreen and an ExpressLRS 2.4 GHz radio system. Designed primarily for RC airplanes, gliders and helicopters, it also supports drones equipped with compatible ELRS receivers. EdgeTX firmware and a versatile control layout allow pilots to adapt the radio to different models, flight modes and personal preferences.

On this MAX version, metal gimbal assemblies are complemented by aluminium buttons and a CNC-machined scroll wheel. A carbon-look shell gives the radio its distinctive finish. This manufacturer part number identifies an FCC/ELRS version.

AG02 gimbals with adjustable control feel

CNC-machined aluminium AG02 gimbals use Hall-effect sensors to detect stick position. Four ball bearings support smooth movement, while adjustable spring tension and travel allow a personalised setup. Horizontal travel can be adjusted from 30° to 56°, and vertical travel from 38° to 54°. Stick ends use an M4 thread.

These mechanical adjustments let pilots choose resistance and stick travel that suit their grip and flying style. Included low-tension springs provide another way to fine-tune control feel. Interchangeable shoulder switch modules also allow changes to the control layout, including momentary-button configurations.

ExpressLRS Gemini with two integrated antennas

An internal radio system uses two Semtech SX1281 transceivers and supports ExpressLRS Gemini in the 2.4 GHz band. Gemini sends packets simultaneously on two different frequencies, improving their chance of reception when interference affects a link. Full use of this feature requires a Gemini-capable receiver and appropriate settings.

Horizontal and vertical antennas positioned behind the display provide polarization diversity without a protruding external antenna. GX15 MAX also supports F1000 operation with compatible receivers. Up to 16 control channels are available, depending on receiver capabilities and configuration. When using a conventional ELRS receiver, select a radio mode appropriate for its supported features.

Top-mounted 3.5-inch IPS touchscreen

A 480 × 320 IPS touchscreen displays 262,000 colours and offers brightness of up to 600 nits. Its position above the gimbals keeps telemetry, timers and model information visible without hands covering the screen. Physical buttons and a scroll wheel complement touch controls, providing several ways to navigate settings.

An STM32 H7 processor runs EdgeTX firmware and handles menus, model configurations and scripts. GX15 MAX requires EdgeTX version 2.12.0 or later. Its configuration options suit pilots who want individual control arrangements for different aircraft and convenient switching between model profiles.

Storage, motion inputs and expansion

Built-in flash storage provides 512 MB of capacity, with support for a 32 GB microSD card formatted as FAT32. Inserting a memory card disables onboard flash storage, so these work as alternative storage locations. A microSD card is not included.

An integrated gyroscope allows radio tilt to serve as an additional control input. Configured functions can include triggering logical switches, controlling camera movement or activating telemetry voice prompts. A built-in microphone is reserved for future functionality. A JR-compatible external module bay allows a separate transmitter module to be added when required by a particular model or radio system.

USB-C connectivity, cooling and battery options

USB-C supports charging, simulator connectivity, data transfer and firmware updates. This allows pilots to use their regular radio for flight practice on a computer as well. An internal fan and aluminium heat sinks help remove heat from electronics during extended sessions.

Operating voltage is 6.6–8.4 V. Supported power options include a 7.4 V two-cell LiPo battery, two 3.7 V 18650 lithium-ion cells or a compatible RadioMaster 21700 5000 mAh battery pack. An 18650 battery tray is supplied, but batteries must be purchased separately. Operating time depends on battery capacity and radio settings.

Package contents

Included are a GX15 MAX radio controller, Signature Carry Case, an 18650 battery tray, two replacement shoulder panels, a USB-C cable and a screen protector. Accessories also include a 1.5 mm hex wrench, four low-tension gimbal springs, two gimbal stick set screws, four 6 mm switch-hole grommets, a neck strap, stickers and a user manual.

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