Giving a Multimeter Wi-Fi... Because Why Not?

Published at : 23 Dec 2025

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Affiliate links:
Multimeter: https://s.click.aliexpress.com/e/_c2vyVTtV
Test Leads Kit: https://s.click.aliexpress.com/e/_c3sWWwSb
Logic Analyzer: https://s.click.aliexpress.com/e/_c4BwbomF
ESP32: https://www.dfrobot.com/product-2778.html?tracking=7ysCNw2L8l1NJkQJOMiW3wq3Yw6h3fxYRRdtcFSMqR5CBJscXExirYTZbv3z03ZE

Code:
https://github.com/FireMarshmellow/DMM_Web_interface
https://github.com/840922704/BLE_DMM_Client

Information:
https://github.com/ludwich66/Bluetooth-DMM/wiki
https://justanotherelectronicsblog.com/?p=930
https://fccid.io/2AR7VF-9788/User-Manual/15-F-9788-UserMan-r1-4697443.pdf

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⏱️ Chapters
00:00 Introduction and Idea
00:24 Testing the Bluetooth Multimeter
01:28 Disassembly and Teardown
02:20 Guided Meditation Sponsor – JLCPCB
05:24 Research and GitHub Discoveries
06:14 Replacing Bluetooth with ESP32
08:46 Logic Analyzer Setup and Findings
10:03 Triggering Data Transmission
11:46 Decoding and Matching Data
12:40 Web Server and Display Success
13:42 Powering the ESP32 from Batteries
15:00 Final Assembly and Demo

🎉 Video Summary
I wanted to get readings from my cheap Bluetooth multimeter onto a web page, so I replaced its internal module with an ESP32. I used a logic analyser to decode the serial protocol and a boost converter to power the ESP32 from the multimeter's batteries, resulting in a Wi-Fi multimeter that hosts its own web server.

🏷️ Tags
#diy #electronics #esp32 #project #maker #hacking
#multimeter #wifi #bluetooth #iot #reverseengineering
#logic #analyzer #esp32project #teardown #serialprotocol
#pulseview #aliexpress #jlpcb #webserver #tps61023