October 6, 2026

ESPsoup: Turn an ESP32-C5 into a 2.4 & 5 GHz Pocket Scanner with a Connected Phone or PC

Thank you to Peter Holzhauser for writing in and sharing with us his latest open-source project, 'ESPsoup'. Peter has written in previously to share his Android app, V2X2MAP, which detects and plots vehicle V2X (car-to-car) communications used by some modern cars. His new project, ESPsoup, combines an ESP32-C5 and a connected PC or phone into a fully featured scanner for the 2.4 GHz and 5 GHz bands.

ESPsoup has various features including a live spectrum view up to 80 MHz wide, a sweep mode to monitor larger bandwidths, a GPS-enabled heatmapping tool, Bluetooth analysis tools, an AirTag detector, WiFI analysis tools, a car-to-car V2X monitor, a smart home sensor reader, a drone remote ID detector, a microwave oven detector, and an analog FPV video demodulator and display.

The website notes that if you want to monitor multiple FPV drone video channels, up to eight ESP32-C5s have been tested to work together on a single USB hub connected to a PC.

Peter notes that he is planning to add RTL-SDR support to ESPsoup in approximately two weeks, so keep an eye out on their website for updates.

ESPsoup screenshots from a mobile device.

June 18, 2026

V2X2MAP: Visualize European 5.9 GHz V2X Vehicle and Traffic Signal Messages with an Android App and ESP32

Thank you to Peter for writing in and sharing news about his Android app called V2X2MAP, which makes Vehicle-to-Everything (V2X) radio traffic visible on a live map via an attached ESP32 board. The app is not free but costs only a small US$2.49 fee.

V2X is a cooperative wireless system in which vehicles and roadside infrastructure continuously broadcast small messages in the 5.9 GHz band. Equipped cars broadcast their position, speed, heading, and brake status about 10 times per second, while traffic signals broadcast their phase and timing, lane geometry, and event-driven hazard warnings. It can be thought of as something like ADS-B or AIS for cars, though at a much shorter range (typically a couple of hundred meters), with the added feature that roadside infrastructure also transmits.

V2X is designed to enhance vehicle safety, allowing vehicles to know about obstacles, traffic phases, and road geometry in advance. Currently, two incompatible standards are used: the older DSRC (Wi-Fi-based) and the newer C-V2X (cellular-based). Most markets are moving towards C-V2X because it provides short and long-range communications.

The V2X2MAP Android app works together with a $20 Waveshare ESP32-C5 board, which has an onboard 5.9 GHz WiFi 6 radio. The ESP32 receives the older Wi-Fi DSRC signals, particularly the ITS-G5 standard, which appears to be used only in Europe. Once running, V2X2MAP and the ESP32 decode the surrounding V2X broadcasts and plot live vehicles, hazard warnings, and traffic-light countdowns on a map of your immediate area.