HappyModel ES24TX Pro 1000mW 2.4G ExpressLRS Micro TX Module Instruction Manual

5.1 Physical Installation

1. Ensure your radio transmitter is powered off.
2. Locate the Micro JR bay on the back of your compatible OpenTX radio transmitter (e.g., TX16S, QX7, TX12, X9D).
3. Carefully insert the ES24TX Pro module into the JR bay, ensuring it is seated firmly.
4. Attach the provided antenna to the SMA connector on the module. Hand-tighten only; do not overtighten.

Image 3: The ES24TX Pro module correctly installed in the JR bay of a compatible radio transmitter.

5.2 Radio Transmitter Configuration

1. Power on your radio transmitter.
2. Navigate to the Model Setup menu in OpenTX/EdgeTX.
3. Scroll to the "External RF" section.
4. Set the External RF mode to "CRSF" (Crossfire) as ExpressLRS uses the CRSF protocol.
5. Ensure the internal RF module is turned off if you are using the external ELRS module exclusively.

5.3 Firmware Flashing (Advanced Users)

While the module comes with pre-installed ExpressLRS firmware, advanced users may wish to update or flash custom firmware. This typically involves:

• Accessing internal switches: Some users report needing to open the module casing to access internal switches for flashing. Refer to community resources or HappyModel documentation for specific instructions for your module version.
• Connecting via USB-C: The module features a USB-C port for firmware updates.
• Using the ExpressLRS Configurator: Download the latest ExpressLRS Configurator software to compile and flash firmware.

Image 4: Internal view of the ES24TX Pro module, showing the heatsink and potential access points for advanced configuration.

6.1 Binding to a Receiver

To establish a connection between the ES24TX Pro module and an ExpressLRS receiver:

1. Ensure both the TX module and the receiver are powered on.
2. Put the receiver into binding mode (typically by cycling power three times or pressing a bind button). The receiver's LED will usually flash rapidly.
3. On your radio transmitter, navigate to the ExpressLRS LUA script (usually found in the Tools menu).
4. Select the "Bind" option within the LUA script. The TX module's RGB LED will indicate binding status.
5. Once bound, the receiver's LED should become solid, and the TX module's LED will indicate a successful connection.

6.2 Adjusting Power Output

The ES24TX Pro supports adjustable power output up to 1000mW. Adjusting power is crucial for optimal performance and to prevent overheating.

1. Access the ExpressLRS LUA script on your radio transmitter.
2. Locate the "Power" or "TX Power" setting.
3. Select the desired power level (e.g., 10mW, 25mW, 100mW, 250mW, 500mW, 1000mW).
4. For indoor flying or short ranges, lower power settings (e.g., 100mW) are often sufficient.
5. For outdoor flying or longer ranges, higher power settings (e.g., 250mW or above) may be used.
6. Important: When using higher power settings, ensure the built-in cooling fan is active to prevent overheating. The fan can usually be enabled or configured within the LUA script.

6.3 RGB LED Status Indicators

The RGB LED on the module provides visual feedback on its operational status. Refer to the official ExpressLRS documentation for a complete list of LED patterns and their meanings. Common indications include:

• Solid Green: Connected and operating normally.
• Flashing Green: Binding mode or waiting for connection.
• Solid Red: Error or fault condition.
• Flashing Red: Overheating warning or low voltage.

8.1 Module Not Powering On / No LED

• Check Connection: Ensure the module is fully seated in the JR bay of your radio transmitter.
• Radio Power: Verify that your radio transmitter is powered on and has sufficient battery charge.
• Radio Configuration: Confirm that the external RF module is enabled in your radio's model settings.
• Module Fault: If the module previously worked and now shows no signs of life, it might be faulty.

8.2 Unable to Bind to Receiver

• Firmware Mismatch: Ensure both the TX module and the receiver are running compatible ExpressLRS firmware versions. It is recommended to use the same major version.
• Binding Phrase: If using a binding phrase, ensure it is identical on both the TX module and the receiver.
• Binding Procedure: Double-check that you are following the correct binding procedure for both the receiver and the TX module (e.g., power cycling the receiver correctly).
• Proximity: Keep the receiver close to the TX module during the binding process.

8.3 Module Overheating

• Enable Fan: Ensure the built-in cooling fan is enabled and operating, especially when using higher power output settings (250mW and above). This can usually be configured via the ExpressLRS LUA script.
• Airflow: Ensure the fan intake and exhaust vents are not obstructed.
• Power Setting: Reduce the TX power output if overheating persists, especially in warm environments or during prolonged use.

8.4 Intermittent Connection / Range Issues

• Antenna Check: Verify that the antenna is securely connected to the module and is not damaged.
• Receiver Placement: Ensure the receiver antenna(s) on your drone/aircraft are properly positioned and not obstructed by carbon fiber or other components.
• Power Output: Increase the TX power output if operating at longer ranges, ensuring the cooling fan is active.
• Environment: Be aware of potential interference from Wi-Fi, other 2.4GHz devices, or physical obstructions in your flying area.