ESP32 Walkie-Talkie

A walkie-talkie no longer has to rely on traditional radio hardware to feel familiar. A new ESP32-based project shows how two small devices can communicate directly over Wi‑Fi without requiring a radio license. The setup uses ESP-NOW, the direct device-to-device communication method in the ESP32 ecosystem, to send audio without an access point or any extra network infrastructure. That makes the project unusually simple for a push-to-talk system built around maker-grade parts. What makes the system different Instead of using the same radio frequencies as conventional handheld transceivers, the project moves voice traffic through Wi‑Fi between modules. The result is a compact communication tool that behaves much like a classic walkie-talkie, but avoids the licensing concerns associated with standard radio operation. Hackster.io first highlighted the project, which comes from the Tech Talkies YouTube channel. At its core, it turns a small ESP32 board into a push-to-talk communicator that two units can share. The main hardware The build centers on the Seeed Studio XIAO ESP32S3 Sense, chosen because it includes a built-in PDM microphone. That removes the need for an external microphone and keeps the hardware stack compact. For audio output, the project uses a MAX98357A I2S amplifier paired with a small speaker. This allows received audio to play back directly on the opposite unit. The user experience stays close to that of a normal walkie-talkie through a push-to-talk button. Press and hold the button to transmit voice, then release it to return to listening mode. How the audio link works The most important part of the build is audio streaming over ESP-NOW. Because the connection happens directly between devices, the two units can pair and communicate without an access point. The project also uses a thread-safe audio ring buffer. Its role is to store incoming audio and hand it off to the main loop for playback, which helps avoid I2S corruption from the Wi‑Fi callback thread. That detail matters because real-time voice transmission is sensitive to processing interruptions. Without careful buffer handling, the result can be broken or distorted audio at the receiving end. Setup is kept simple Both boards can run the same firmware, and each one identifies its own MAC address at boot to decide whether it should act as Device 1 or Device 2. This reduces manual configuration and makes the build easier to reproduce. The approach also lowers the barrier for new ESP32 users who want to try a communication project like this. With less setup work, the project becomes more accessible to hobbyists who want to experiment quickly. Range depends heavily on the antenna In practical use, the antenna matters a great deal. The built-in antenna on the board reportedly loses connection when the two units are separated by a few rooms. Using an external antenna improves the situation significantly. With that upgrade, the connection can reportedly be maintained at around 200 meters in open outdoor conditions. That range suggests the project is more than a bench-top experiment. For short-distance communication in open space, it already behaves like a simple handheld communication device. Even so, it is still not the same as a professional radio-based walkie-talkie. Since the system depends on direct Wi‑Fi communication between modules, performance will vary with the environment and the quality of the antenna used. Why it stands out Projects like this keep older communication ideas relevant in a world dominated by smartphones. They also offer a practical way to learn about ESP32 integration, digital audio, I2S amplifiers, push-to-talk controls, and real-time data handling in one build. For makers, the XIAO ESP32S3 Sense becomes an especially interesting centerpiece because of its built-in microphone, ESP-NOW support, and automatic peer setup. The result is a compact project that combines convenience with clear technical value. All of the materials needed to build the system have been shared through the project’s GitHub page. Anyone interested can inspect the firmware and assembly details to create a similar wireless walkie-talkie setup. Source: www.xda-developers.com

ESP32 Turns Into a License-Free Walkie-Talkie, And It Can Reach 200 Meters