You Can Build Your Own ESP32 Walkie-Talkies

If you have spent any amount of time in the maker community, then you have certainly come across plenty of ESP32-powered projects. These little chips show up in everything from basic LED flashers to desktop robots and handheld gaming systems. But as versatile as they are, makers continue to find new and unexpected ways to put them to work. YouTuber Tech Talkies recently demonstrated one particularly clever example by using a pair of ESP32 development boards to build fully functional walkie-talkies.

While traditional walkie-talkies rely on dedicated radio hardware and licensed frequency bands, this project takes a different approach. Instead of transmitting voice over conventional radio frequencies, the devices communicate using ESP-NOW, a low-latency wireless protocol built into Espressif's popular microcontrollers. In this way, the devices can exchange voice messages directly without requiring a Wi-Fi router or internet connection.

At the core of each unit is a Seeed Studio XIAO ESP32S3 Sense development board. This module was chosen both for its small footprint and the available microphone add-on board, which handles voice capture. The particular version used in the project also supports an external antenna connection, which is important for extending communication range.

Audio playback is handled by a MAX98357 I2S amplifier module paired with a small 23mm speaker. The amplifier receives digital audio data from the ESP32 and converts it into an analog signal powerful enough to drive the speaker. Power comes from a removable 18650 lithium-ion battery mounted in a battery shield that also provides charging functionality and can serve as a power bank for charging other devices.

A push button acts as the push-to-talk control, and a separate slide switch powers the entire device on and off. These components are soldered onto a small 3x7-cm prototyping board alongside the amplifier module and supporting circuitry. During assembly, the creator points out an interesting quirk of the battery shield: its onboard switch only controls the USB output, not the board's main power rails. Because of this, a dedicated external switch must be wired into the system to completely disconnect power.

Before any hardware assembly begins, the firmware is loaded onto each ESP32 using the Arduino IDE. The two walkie-talkies are paired by reading each board's unique MAC address and inserting those identifiers into the project's configuration files. This creates a dedicated communication link between the two handsets.

The electronics are then installed inside custom 3D-printed enclosures along with the speaker, battery shield, and antenna hardware. After everything is secured and wired together, the finished units resemble commercial handheld radios.

Field testing demonstrated that the design was quite effective. In an open outdoor environment, the walkie-talkies maintained communication at distances exceeding 200 meters. If you’d like to build your own, check out the video below for some tips.