A laptop and an SDR dongle is still the default radio lab. Maker SAMS0N1TE is collapsing that stack into a pocket multitool called LakeShark: open-source firmware that turns ESP32-P4 boards into portable scanners for ADS-B, P25, FM, pagers, LoRa and more. Hackster covered the project, and the code lives on GitHub under GPL-3.0.
ESP32-P4 boards, SX1262 or LR2021
Supported hardware includes the LILYGO T-Display P4 (4.1-inch AMOLED, GPS, IMU) and Waveshare ESP32-P4 boards. With an SX1262 the focus is LoRa. With Semtech's LR2021 the same handheld can take P25 digital voice, analog FM, ADS-B aircraft beacons and pager traffic without a separate SDR, and recent firmware even runs specialised DSP jobs such as FFT and frequency sweeps on the radio's own processor. Boards without that radio can attach an RTL-SDR over USB for P25 Phase I trunking, FM, POCSAG and ADS-B, with experimental HackRF One support still maturing.
Beyond scanning, the app set covers MeshCore, sub-GHz capture and replay, FT8, GPS tools, offline maps and a music player. An optional MIX-RF keyboard for the T-Display P4 adds physical keys plus CC1101, nRF24 and NFC. Headless Waveshare boards can be driven from a serial terminal or a Flipper Zero, and a LakeShark Desktop mode lets apps run in windows on a PC while the P4 still does the RF work.
Our take
The interesting bet is putting a capable MCU next to a multi-protocol sub-GHz radio and treating the laptop as optional. That is a different shape from "ESP32 plus LoRa module for telemetry only." If you are starting with a simpler LoRa link before jumping to LakeShark, our SX1278 LoRa with ESP32 guide covers the SPI radio path, and for another pocket radio that decodes real on-air signals see Fenix on ESP32-S3.
Image credit: SAMS0N1TE / Hackster, cropped and resized.
About the author: Aswinth Raj is an electronics engineer and the editor of CircuitDigest, where he has published more than 150 hands-on projects and tutorials across Arduino, PIC, ESP32, Raspberry Pi and EV battery systems. He selects the stories on this page for what engineers and makers can actually learn or build from. Connect on LinkedIn
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