RC TX Transmitter Modules

An external TX transmitter module is a device mounted in a special module bay on the back of a compatible RC radio. It allows you to expand the capabilities of your radio or adapt it to specific needs. In the context of the ExpressLRS (ELRS) system, the main reasons for using an external TX module are:

• Adding ELRS Support: If your RC radio does not have a built-in ELRS module (e.g., it only has a 4-in-1 module or an older protocol), an external module allows you to take advantage of the ELRS system (range, low latency).
• Using a Different Frequency: If your radio has a built-in 2.4GHz ELRS module, but you want to fly long distances using the 868MHz band, you can install an external 868MHz ELRS module.
• Higher Output Power: External modules often offer higher maximum transmission power (e.g., 500mW, 1W or more) than built-in modules, resulting in even greater range (remember legal power limits!).
• Specialized Features: Some advanced features, like the Gemini mode (simultaneous operation on 2.4GHz and 868MHz for maximum reliability), require dedicated external modules.

External modules come in two main bay size standards: JR (larger, in older and bigger radios) and Nano (smaller, in newer and more compact radios).

When choosing an external ELRS transmitter module, pay attention to several key parameters:

• Radio Compatibility: Ensure the module fits the bay in your radio (JR or Nano). Also check if your radio supports the communication protocol with the module (usually CRSF).
• Operating Frequency: Choose the module for the band you need and that is compatible with your ELRS receivers: 2.4GHz (universal, fast), 868MHz (long range/penetration in EU), or a Gemini module (dual-band for maximum reliability).
• Output Power: Modules offer various, usually adjustable, power levels (e.g., from 25mW to 1W or more). Higher power gives longer range but consumes more energy and generates more heat. Always use power levels compliant with local regulations!
• Cooling: At higher powers (e.g., 500mW+), effective module cooling is important – some models have built-in fans (active cooling), others rely on heatsinks (passive).
• Additional Features: Some modules have a built-in OLED screen, joystick, or buttons that facilitate configuring ELRS parameters without using LUA scripts on the radio.
• Brand and Support: Choose modules from reputable manufacturers offering regular ELRS firmware updates, e.g., BetaFPV, HappyModel, Radiomaster.

An external transmitter module is a great way to expand the capabilities of your RC radio. Wondering which ELRS module will fit your RadioMaster or Jumper radio? Do you need the JR or Nano version? What power output should you choose, and do you need active cooling? What exactly is Gemini mode?

If you have doubts about choosing the right ELRS TX module, contact us! We'll help you select hardware compatible with your radio and receivers. You can find our contact details on the Contact Us page.

At Avifly, we offer a selection of popular ELRS TX modules, available with fast shipping from our warehouse in Poland.

Expand your radio's capabilities with ELRS modules from Avifly! 📶🔥