Signal & Solder · 18 August 2026

ESP‑GMF v1.0, AirMeter wireless mod, and cheap logic analyzers (Jul 31, 2026)

🔧 Tool of the Week

ESP‑GMF (Espressif General Multimedia Framework)

A lightweight pipeline framework for audio/video/image streaming on ESP32-class chips — useful if you’re building cameras, audio devices, or on-device streaming/AI demos that need low RAM and composable elements. Start with the examples and the component registry on GitHub. 🔗 https://github.com/espressif/esp-gmf (github.com)

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🛒 Deals & Finds

  • ANENG AN870 (19999‑count) multimeter

– Cheap, feature-packed bench/field meter that’s easy to mod (used in the build below). Good for a first reliable TRMS DMM. 🔗 Banggood listing / ANENG AN870 (banggood.com)

  • 24MHz 8‑ch USB logic analyzer (Saleae‑style clone)

– $10–$20 kit that works with Sigrok/PulseView for I²C, SPI, UART debugging — the best value instrument after a DMM. 🔗 AliExpress / USB Logic Analyzer 24MHz 8CH listing (en.aliradar.com)

  • HC‑12 433MHz serial transceiver (single‑board modules)

– Long‑range, UART‑style link for simple radio telemetry (used in the AirMeter build). Cheap and widely available on AliExpress/retailers. 🔗 AliExpress product / HC‑12 listings (alitools.io)

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🧪 Cool Build

AirMeter — wireless mod for the ANENG AN870 (reads the multiplexed LCD)

A practical reverse‑engineering project: the build reads the ANENG’s 19 multiplex LCD lines with a small comparator board + RP2040, radios the frame data via HC‑12 to an ESP32‑C3 receiver that serves a browser dashboard / OBS overlay. Great example of dealing with non‑UART instrument outputs and turning them into a usable stream. 🔗 Build guide (Bits und Bolts) (bitsundbolts.com)

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📚 Worth Reading

  • 20 FPS on e‑paper display without help – practical notes and demo on pushing e‑paper refresh rates (useful if you drive displays from constrained MCUs). 🔗 Hackaday: 20 FPS on e‑paper (hackaday.com)

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⚡ Quick Hits

  • Espressif announced an Aliro SDK (NFC Aliro reader examples and an Aliro+Matter demo). Good if you’re building access / lock demos. 🔗 [Espressif Aliro SDK announcement]. (developer.espressif.com)
  • Sigrok / PulseView nightly builds and downloads (if you rely on cheap logic analyzers, grab the AppImage or nightly builds). 🔗 [sigrok downloads]. (sigrok.org)
  • Hackaday: small ESP32 “plane radar” desktop display (neat reference for small‑display networked gadgets). 🔗 [Hackaday: ESP32 plane radar]. (hackaday.com)

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📺 Cool Videos

  • I Made This Budget Multimeter Wireless!

– Short, clear walkthrough and demo of AirMeter’s build and dashboard. 🔗 YouTube video (Bits und Bolts) (bitsundbolts.com)

  • Bad Apple at 20fps on e‑paper (demo)

– Fast e‑paper demo referenced in the e‑paper writeup — useful to see the practical limits and artifacts. 🔗 YouTube short: Bad Apple on e‑paper (20fps demo) (hackaday.com)

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