In case you have spent any period of time within the maker group, then you’ve actually come throughout loads of ESP32-powered initiatives. These little chips present up in all the pieces from primary LED flashers to desktop robots and handheld gaming methods. However as versatile as they’re, makers proceed to search out new and sudden methods to place them to work. YouTuber Tech Talkies just lately demonstrated one notably intelligent instance through the use of a pair of ESP32 improvement boards to construct totally useful walkie-talkies.
Whereas conventional walkie-talkies depend on devoted radio {hardware} and licensed frequency bands, this challenge takes a unique method. As an alternative of transmitting voice over typical radio frequencies, the units talk utilizing ESP-NOW, a low-latency wi-fi protocol constructed into Espressif’s in style microcontrollers. On this method, the units can alternate voice messages instantly with out requiring a Wi-Fi router or web connection.
An antenna extends communication vary (📷: Tech Talkies)
On the core of every unit is a Seeed Studio XIAO ESP32S3 Sense improvement board. This module was chosen each for its small footprint and the obtainable microphone add-on board, which handles voice seize. The actual model used within the challenge additionally helps an exterior antenna connection, which is vital for extending communication vary.
Audio playback is dealt with by a MAX98357 I2S amplifier module paired with a small 23mm speaker. The amplifier receives digital audio knowledge from the ESP32 and converts it into an analog sign highly effective sufficient to drive the speaker. Energy comes from a detachable 18650 lithium-ion battery mounted in a battery defend that additionally supplies charging performance and might function an influence financial institution for charging different units.
A push button acts because the push-to-talk management, and a separate slide swap powers your entire system on and off. These parts are soldered onto a small 3×7-cm prototyping board alongside the amplifier module and supporting circuitry. Throughout meeting, the creator factors out an fascinating quirk of the battery defend: its onboard swap solely controls the USB output, not the board’s principal energy rails. Due to this, a devoted exterior swap should be wired into the system to utterly disconnect energy.
Putting in the {hardware} within the case (📷: Tech Talkies)
Earlier than any {hardware} meeting begins, the firmware is loaded onto every ESP32 utilizing the Arduino IDE. The 2 walkie-talkies are paired by studying every board’s distinctive MAC handle and inserting these identifiers into the challenge’s configuration information. This creates a devoted communication hyperlink between the 2 handsets.
The electronics are then put in inside customized 3D-printed enclosures together with the speaker, battery defend, and antenna {hardware}. After all the pieces is secured and wired collectively, the completed items resemble business handheld radios.
Discipline testing demonstrated that the design was fairly efficient. In an open outside surroundings, the walkie-talkies maintained communication at distances exceeding 200 meters. When you’d wish to construct your individual, try the video beneath for some ideas.