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TinkerNews Podcast #61: XGO Duck, Tiny Game Worlds, and a Local AI Thermostat

TinkerNews — Tue, 10 Nov 2026 02:21:43 +0000

The TinkerNews podcast has a new episode: TinkerNews Podcast #61: XGO Duck, Tiny Game Worlds, and a Local AI Thermostat.

TinkerNews, a free weekly DIY electronics newsletter. Every Sunday's issue curates the best DIY electronics builds on the web (ESP32, Arduino, Raspberry Pi, robotics, IoT), and this podcast is its audio edition.

🎧 Listen to the episode: https://www.tinkernews.com/issues/61-xgo-duck-tiny-game-worlds-and-a-local-ai-thermostat?utm_source=devto&utm_medium=article&utm_campaign=podcast

TinkerNews #61: XGO Duck, Tiny Game Worlds, and a Local AI Thermostat

TinkerNews — Tue, 10 Nov 2026 02:15:01 +0000

Originally published in TinkerNews Issue #61. Free weekly DIY electronics.

XGO Duck, Tiny Game Worlds, and a Local AI Thermostat

Issue 61 explores practical edge-computing builds: control an XGO Duck from a browser, run neural game worlds on a Pico 2 W, and let an Arduino UNO Q manage a local AI…

🤖 Lead build: Browser-Controlled XGO Duck on Arduino Uno Q

A browser becomes the control panel for an XGO Duck running on Arduino Uno Q. This runtime combines learned ONNX motion policies with Python control and STM32 feedback loops. It handles calibration, recovery, skating, servo safety, and practical diagnostics for makers working with compatible hardware.

Read the build → (via github.com)

⚡ Arduino

Connect the UNO Q’s Linux and STM32 Sides

A potentiometer on A5 sets the UNO Q’s built-in LED brightness through messages between Python on Debian Linux and an STM32 sketch. This build shows how the Bridge moves data, when to use call() or notify(), why provide_safe() matters, and how a WebSocket page can add browser control.

Read the build → (via mischianti.org)

An Arduino UNO Q Runs a Local AI Thermostat

An Arduino UNO Q runs a small language model locally, reads a simulated temperature, and controls an LED fan. Python gives the model limited tools, while the STM32 keeps deterministic control of the hardware. The build also measures startup delay, response speed, memory use, and model size.

Read the build → (via mischianti.org)

🔧 DIY Electronics

A Mecha Desk Buddy with Drawers and a Touchscreen Face

Thirty-three printed parts form a small mecha organizer with storage for a phone, pens, SD cards, and circuit boards. An ESP32-S3 drives its 2.8-inch touchscreen, while Arduino and LVGL 9 provide blinking eyes and six expressions. The result combines useful desk storage with a friendly animated interface.

Read the build → (via hackaday.io)

📶 ESP32

Marelleo: An ESP32 Story Box for NFC Figurines

Marelleo turns an NFC-tagged figurine into a story, song, or radio control. An ESP32 handles detection, Wi-Fi, audio playback, and updates inside a child-ready box. The build moved from breadboard to perfboard and custom PCB, with battery safety, mechanical failures, and recovery testing shaping each revision.

Read the build → (via zebra.rodeo)

Kube32 Brings kubectl to ESP32 Clusters

Use kubectl to place WebAssembly apps on a small ESP32-S3 cluster. Kube32 pairs a PSRAM-equipped control plane with worker boards such as the M5Stack Cardputer, then treats displays, sensors, storage, and input devices as managed resources. A simulator and practical examples make the setup easier to try.

Read the build → (via github.com)

Build a Browser-Controlled ESP8266 Relay

A NodeMCU ESP8266 can serve a small control page over 2.4 GHz Wi-Fi and switch a relay from any browser on the same network. The project uses one relay, one status LED, and a short Arduino sketch, with clear limits around security, local access, and mains wiring.

Read the build → (via anilestore.com)

ESP32-S3 Rotary Universal Timer

Four timer scales, a rotary encoder, and a circular display give this CrowPanel project a simple way to set and watch time pass. An external buzzer adds three audible alerts at zero, while framebuffer drawing keeps the display smooth. Arduino users need specific ESP32 and graphics library settings.

Read the build → (via hackaday.io)

Inside an Open ESP32-S3 Board Designed in KiCad

Built around Espressif's ESP32-S3-WROOM-1-N8R8, this open board packages the schematic, PCB layout, custom KiCad libraries, BOM, Gerbers, drill files, and documentation in one repository. The design is ready for inspection and fabrication, while board assembly, testing, bring-up, and firmware work remain future steps.

Read the build → (via github.com)

🌐 IoT

Build a 3D Home Assistant Dashboard

Home Assistant usually shows devices in cards and lists. NeonPlan 3D puts them inside a model of your home, where rooms, lights, blinds, cameras, sensors, energy equipment, and warnings appear in place. You draw or import the plan, link areas, then publish reusable views for dashboards and wall tablets.

Read the build → (via github.com)

Repurpose an Old Echo for Home Assistant

An old Echo can keep its far-field microphones and local wake-word hardware while dropping Alexa's cloud connection. hassmic routes speech through Home Assistant Assist, with several Echos choosing one responder locally. It also supports local music, Bluetooth, automations, and Show displays, though installation involves firmware work and real brick risk.

Read the build → (via github.com)

Build a Live 3D Smart-Home Controller

House Control turns a JSON floor plan into a live 3D control surface for lights, air conditioners, scenes, and sensors. Native Mac and iPhone apps connect Smart Life, Home Assistant, Philips Hue, and Apple Home, while simulated devices, local storage, and HTTP or MCP access keep experimentation practical.

Read the build → (via github.com)

Marstek Venus E Meets Home Assistant

A LilyGO T-CAN485 reads a Marstek Venus E over RS485 and sends local battery data to Home Assistant through ESPHome. The build adds energy history, warnings, runtime estimates, and operating controls, while keeping the battery connection, firmware version, secrets, and ESP32 hardware limits in view.

Read the build → (via github.com)

ESP8266 Wi-Fi Bridge for Pylontech Batteries

PylontechMonitoring connects a battery stack’s RS-232 console to a Wemos D1 Mini through a MAX3232 transceiver. The ESP8266 sends battery and module readings to MQTT, where Home Assistant can create sensors automatically. A browser console, JSON endpoint, and wireless firmware updates support maintenance and custom dashboards.

Read the build → (via github.com)

SpiderBridge Puts GGS Control on Home Assistant

A roughly €10 ESP32 can sit between a Spider Farmer GGS controller and Home Assistant, keeping control on your network. SpiderBridge installs through a browser, provisions the controller over Bluetooth once, then handles Wi-Fi, TLS, MQTT, cloud forwarding, and local automation without a Raspberry Pi.

Read the build → (via github.com)

Turn a Cheap Wi-Fi Clock Into an ESP32 Display

A closed-firmware HU-058D clock becomes a Home Assistant display when an ESP32-WROOM-32 takes over its RGB panel. The build keeps the case and LEDs, adds custom effects and controls, and can expose temperature, light, and buzzer hardware, depending on the firmware configuration and board variant.

Read the build → (via github.com)

🍓 Raspberry Pi

A Pico 2 W Runs Its Own Tiny Game Worlds

Five small games run on a Raspberry Pi Pico 2 W while two neural networks generate frames and choose actions. The project combines grid tokens, a reused transformer block, int8 weights, game-aware decoding, and dual-core scheduling. Results are strong on simple games, though Pac-Man and Doom-lite still expose clear limits.

Read the build → (via github.com)

A Raspberry Pi 5 Knowledge Box for Offline Use

A Raspberry Pi 5, NVMe SSD, and local Wi-Fi network can carry Wikipedia, maps, medical references, repair guides, and emergency material without internet access. HAS_PrepperDisk adds Internet-in-a-Box, Kiwix, automated downloads, a browser homepage, and health checks for use in remote or disrupted settings.

Read the build → (via github.com)

Raspberry Pi CRT Tracks Spacecraft in Retro Mission Console

A Raspberry Pi drives a 640x480 mission-control display on a composite CRT, while Rust gathers spacecraft positions, telemetry, schedules, and sky data. mctl offers interactive pages, unattended kiosk scenes, offline caching, replay, and several period-style themes. A Pi 3B+ handles it through software rendering at modest frame rates.

Read the build → (via github.com)

Build a Raspberry Pi Marine Radar Display

At the navigation station, a Raspberry Pi combines Raymarine Quantum radar data with Signal K readings, AIS contacts, and anchor monitoring. Exodus Radar renders the view on an HDMI screen or browser, while Python services handle decoding and control. It remains a Quantum-specific, experimental aid, not certified navigation equipment.

Read the build → (via github.com)

Build an RFID Reader for Raspberry Pi 5

Older RC522 tutorials often fail on Raspberry Pi 5 because they depend on RPi.GPIO. This build uses SPI through spidev and reset control through gpiod. Wire the reader at 3.3 V, read card UIDs, then use those values for a hobby access project. UID matching suits demonstrations, not high-security systems.

Read the build → (via raspberry.tips)

🤖 Robotics

$1.50 FOC Board Builds a Tiny 10:1 Robot Joint

A 1503 brushless gimbal motor, a roughly $1.50 four-layer FOC board, and a printed 10:1 gearbox make a compact robot joint. The design is open hardware, though its firmware remains open loop and needs configuration work before it can serve as a dependable servo.

Read the build → (via github.com)

MOSS: An Open-Source Litter-Picking Rover

MOSS is a tracked, 3D-printed rover that follows a person and collects small litter with a robotic arm. Its current prototype can drive and demonstrate pick-and-drop handling under teleoperation. Open hardware files, several computer choices, and simulation tools make it a practical project for experienced robotics makers.

Read the build → (via github.com)

🔩 Recommended reads

ESP32 Snake Game with MPU6050 and OLED

Embedded Nerd's motion-controlled build: MPU6050, OLED and a complete Arduino sketch. The tutorial we picked for this swap, wired end to end.

Read the build → (via embeddednerd.com)

Tindie Blog

What makers actually sell: new gear, seller stories and open hardware news.

Read the build → (via blog.tindie.com)

Circuit Cellar

Embedded design articles from the magazine that has covered microcontrollers since 1988.

Read the build → (via circuitcellar.com)

🔩 From the bench

Voltage divider calculator

One of 19 free no-signup bench tools for the projects in this issue.

Read the build →

TinkerNews is a free weekly newsletter with the best DIY electronics builds:
ESP32, Arduino, Raspberry Pi, IoT, robotics and 3D printing.
Subscribe free → tinkernews.com

The capacitor markings that are not microfarads

TinkerNews — Fri, 06 Nov 2026 10:43:54 +0000

A capacitor marked 0.1 MFD is not a 0.1 farad part. It is 0.1 microfarad, which is 100 nanofarad, which is the same thing as the 104 sitting next to it in the drawer. The marking is older than the SI prefix, and that is the whole trap.

Three marking systems cover almost every capacitor on a hobby bench. Two are arithmetic. One is a fossil.

The three digit code

Three digits: the first two are the value in picofarads, the third is how many zeros to add.

104 is 10 followed by four zeros: 100,000 pF = 100 nF = 0.1 µF.
223 is 22,000 pF = 22 nF.
471 is 470 pF.

The result is always picofarads. Divide by 1,000 for nanofarads, again by 1,000 for microfarads (or by 1,000,000 once). Most people learn 104 = 0.1 µF by repetition and never touch the arithmetic again.

R notation for values below 100 pF

When the multiplier would be zero or negative, the letter takes the decimal point's place:

4n7 is 4.7 nF.
2u2 is 2.2 µF.
R47 is 0.47 pF, not 0.47 µF.
1p0 is 1 pF.

The unit letter is the decimal point. 4n7 is not "four n seven"; it is 4.7 nanofarad.

MFD and MMFD, the markings that look wrong

MFD means microfarad. MMFD means micro-microfarad, which is a picofarad. Both predate the modern µF/pF notation, and both still appear on surplus parts, old schematics, and equipment manuals.

0.1 MFD = 0.1 µF = 100 nF = 104.
0.001 MFD = 1 nF = 102.
MMFD on its own, or .001 MMFD, is a picofarad-scale part.
100 MMFD = 100 pF.

The failure mode is not subtle. Read 0.1 MFD as 0.1 farad and you have a component three orders of magnitude larger than the one the circuit wants. Read MMFD as microfarad and the error goes the other way. Either way the board does not work, and the part usually looks fine.

The traps that are not about the code

Voltage rating is separate. A 104 can be 50 V, 100 V, or 1 kV. The code says nothing about it.
Tolerance changes the part you can substitute. A 104 in a timing circuit may be a 5% or 10% part; a 1% part is a different purchase.
Dielectric matters more than the number. A 100 nF ceramic and a 100 nF film are not interchangeable in filters, oscillators, or anything with a signal across it.
In circuit, expect the neighbours. A capacitor in parallel with a resistor or another capacitor reads differently. Lift one leg before you believe the meter.
Old parts drift. Electrolytics age; a reading far below the marking is information, not proof that the marking is wrong.

The tool

I keep a free reader at tinkernews.com/tools/capacitor-code-calculator that handles the numeric codes, R notation, and legacy MFD/MMFD values, and shows the nearest standard value. It is free, with no signup.

If you would rather call it from a script, the same arithmetic lives in the small library at github.com/tinkernews/electronics-tools.

Next time a drawer label says MFD, read it as microfarad first. The arithmetic is easy; the fossil is the part that trips people.

TinkerNews Podcast #60: Pocket Reflex, ISS Tracking, and E-Paper Adventures

TinkerNews — Tue, 03 Nov 2026 01:46:04 +0000

The TinkerNews podcast has a new episode: TinkerNews Podcast #60: Pocket Reflex, ISS Tracking, and E-Paper Adventures.

🎧 Listen to the episode: https://www.tinkernews.com/issues/60-pocket-reflex-iss-tracking-and-e-paper-adventures?utm_source=devto&utm_campaign=podcast

TinkerNews #60: Pocket Reflex, ISS Tracking, and E-Paper Adventures

TinkerNews — Tue, 03 Nov 2026 01:39:08 +0000

Originally published in TinkerNews Issue #60. Free weekly DIY electronics.

Pocket Reflex, ISS Tracking, and E-Paper Adventures

Issue 60 brings hands-on builds that turn embedded hardware into playful, practical machines: an ESP32 pocket reflex console, a Raspberry Pi dish that tracks the ISS, and…

⚡ Lead build: Pocket Reflex Console With Three Games

A pocket-sized ESP32-C3 console turns a round display, eight RGB LEDs, and two buttons into three quick games. Lightning Tap measures reaction time, Chase the Light tests tracking and decisions, and Duel Mode pits two players against each other. The build includes breadboard testing, custom wiring, firmware, and a PLA enclosure.

Read the build → (via instructables.com)

⚡ Arduino

Build an ESP32 Alarm Clock That Needs a Basket

A mini hoop, ESP32, and IR beam turn snoozing into a shot. This project connects a buzzer, BLE setup, rechargeable battery, custom PCB, and 3D printed mount, while showing how sensor alignment, timing, debounce, antenna clearance, and enclosure design shape a practical interactive device.

Read the build → (via instructables.com)

Build an 8-Channel Arduino RC Link

Two Arduino Nano boards pass eight control channels through nRF24L01 radios. Joysticks, potentiometers, and switches become PWM outputs for servos or an ESC. The build includes a hand-made enclosure, downloadable sketches, and clear pin assignments, while leaving range, calibration, failsafe behavior, and interference testing for the builder.

Read the build → (via instructables.com)

Drive a Scratch-Built RC Car Over the Internet

A hand-cut PVC car uses an ESP-01, Firebase, and a phone app to control its motor and steering through an internet connection. Pen refills form the front pivots, a salvaged gearbox adds wheel torque, and a 3S LiPo powers the electronics. Wi-Fi and Firebase settings need configuring first.

Read the build → (via instructables.com)

A Browser-Controlled 12-DOF Spider Robot

Four printed legs, twelve servos, and two controllers make this spider robot walk, turn, wave, and dance. An ESP32-C3 handles Wi-Fi commands from a browser, while an Arduino Nano manages the servos, foot positions, and gait timing. An OLED adds animated eyes and changing expressions.

Read the build → (via robotlk.com)

BLE Retail Display Timer and Tamper Alarm

A shopper lifting a display product starts a 90-second countdown while movement or an unauthorized removal sounds the alarm. Built around an nRF52840, Zephyr RTOS, BLE, and battery backup, the system sends status and tamper alerts to staff phones without store Wi-Fi or cloud services.

Read the build → (via instructables.com)

🔧 DIY Electronics

MatTris Arcade Packs Six Games Into 280 LEDs

A second generation MatTris turns a 14×20 RGB matrix, an RP2040 Tiny, and six buttons into a pocket arcade. Tetris, Snake, Pong, Breakout, Car Dodge, and Space Invaders share a custom PCB, rechargeable power, and a tinted acrylic case built around the tiny display.

Read the build → (via electronicwings.com)

📶 ESP32

Draw Icons and Scroll Text with a MAX7219 Matrix

Eight binary rows make a smiley or heart on one 8×8 matrix, while four chained modules become a scrolling sign. An Arduino UNO sends SPI data through three control lines, with MD_MAX72XX handling graphics and MD_Parola handling text. Keep brightness low on USB, and use level shifting with an ESP32.

Read the build → (via informaticait.it)

An ESP32 Replaces the Leaf’s Cloud TCU

When NissanConnect EV services disappear, Leaf owners lose remote climate and charging controls. simppeliTCU uses a LilyGO T-2CAN board, protected automotive power, and ESP32-CAN firmware to restore local access through Wi-Fi, MQTT, and Home Assistant. It remains a draft for experienced builders who can handle vehicle wiring and safety.

Read the build → (via github.com)

🌐 IoT

Arduino 4WD Robot With Wi-Fi Radar Mapping

Four TT motors carry an Arduino UNO R4 WiFi through an area while a servo turns an HC-SR04 sensor and sends readings to a browser. Floor markers add waypoint cues, and separate batteries keep motor power apart from the controller. The mapping is SLAM-style, with algorithm details left limited.

Read the build → (via hackaday.io)

Build an ESP32 TinyML Vibration Monitor

Unexpected machine faults often begin as small changes in vibration. This ESP32 project uses an MPU6050, a compact autoencoder, and local TinyML inference to spot those changes without cloud processing or fault labels. A calibrated threshold, onboard indicator, MQTT messages, and browser dashboard make results easier to watch and test.

Read the build → (via projectech.in)

Build an ESP32 Home Assistant Touchscreen Panel

A dedicated ESP32 touchscreen gives each room a simple Home Assistant control point. Flash the panel through a browser, connect it to 2.4 GHz WiFi, and arrange local controls from a web page. Lights, scenes, sensors, cameras, media, and climate information can share one screen.

Read the build → (via github.com)

Gestire: An ESP32 Locker for Shared Lab Equipment

Reserve an FPGA board in Flutter, receive a six-digit PIN, and enter it at an ESP32 locker. Gestire links room and equipment bookings to Flask, SQLite, keypad input, LCD guidance, and relay-controlled compartments, while showing where sensors and stronger recovery would matter in a real installation.

Read the build → (via github.com)

🍓 Raspberry Pi

Give a Raspberry Pi Pico Precise Stepper Motion

A Raspberry Pi Pico, ULN2003 board, and 28BYJ-48 motor make repeatable positioning approachable with MicroPython. The supplied library handles coil sequences and offers commands for steps, target positions, directions, and angles. External motor power and a home sensor remain important considerations for small robotics, turntables, gauges, and sliders.

Read the build → (via randomnerdtutorials.com)

A Raspberry Pi Dish Tracks the ISS

A dish on a portable board follows the International Space Station across the sky. A Raspberry Pi Zero W checks pass predictions, cloud cover, and orbital data, then directs two stepper motors through changing azimuth and altitude. The build turns satellite calculations into visible movement and real nighttime observations.

Read the build → (via workshop88.com)

InkQuest Puts Text Adventures on E-Paper

A rotary encoder, e-paper screen, and ESP32-C3 turn each button press into a new story branch. InkQuest keeps five turns of context, asks Gemini for four choices, and shows the result on a low-power display. Its compact PCB, printed case, and sleep mode support roughly 20 hours of estimated use.

Read the build → (via instructables.com)

Gemma 4 on a 4 GB Raspberry Pi 5

A 4 GB Raspberry Pi 5 runs Gemma 4 E2B offline through LiteRT, with no AI HAT or cloud connection. The model uses about 1.6 GB of RAM and produces roughly 8 output tokens per second. This guide covers setup, storage, cooling, downloads, benchmarks, and the choice between LiteRT and Ollama.

Read the build → (via raspberry.tips)

🤖 Robotics

ESP32 Board for a Robot Fox

Ten servo connections give this ESP32 board a place in a 3D-printed quadruped fox, alongside two DC motor connections, a TFT display, and sensor inputs. The project includes a schematic, Gerber files, and an MPU6050 test sketch for makers developing their own robot electronics.

Read the build → (via pcbway.com)

🔩 Recommended reads

ESP32 Snake Game with MPU6050 and OLED

Embedded Nerd's motion-controlled build: MPU6050, OLED and a complete Arduino sketch. The tutorial we picked for this swap, wired end to end.

Read the build → (via embeddednerd.com)

Tindie Blog

What makers actually sell: new gear, seller stories and open hardware news.

Read the build → (via blog.tindie.com)

Circuit Cellar

Embedded design articles from the magazine that has covered microcontrollers since 1988.

Read the build → (via circuitcellar.com)

🔩 From the bench

Battery sizes for makers

One of 16 free no-signup bench tools for the projects in this issue.

Read the build →

TinkerNews is a free weekly newsletter with the best DIY electronics builds:
ESP32, Arduino, Raspberry Pi, IoT, robotics and 3D printing.
Subscribe free → tinkernews.com

A5 on the FireBeetle 2: ADC2, Wi-Fi and two different modes

TinkerNews — Fri, 30 Oct 2026 12:40:11 +0000

DFRobot lists this board as SKU DFR0975 and says it supports Wi-Fi.[3]

I started with the blanket warning that ADC2 and Wi-Fi do not mix. It hides the useful distinction between the ESP32-S3's oneshot driver and its continuous/DMA driver.[1][2]

The vendor's pinout image labels A5 with ADC2_0.[4] The TinkerNews pinout page maps A5 to IO11 and ADC2_CH0.[5]

Single readings

ESP-IDF's oneshot API gives a single reading on demand.[1] ADC2 is also used by Wi-Fi, and the oneshot driver protects access shared with the Wi-Fi driver.[1]

A read can still return ESP_ERR_TIMEOUT if another driver or peripheral is using the ADC. Espressif says the raw result is invalid after that error.[1]

Continuous capture

Continuous mode samples at high speed and uses DMA to move results into memory.[2] Espressif no longer supports ADC2 DMA on the S3 because of hardware limits and unstable results.[2]

The compatibility option is CONFIG_ADC_CONTINUOUS_FORCE_USE_ADC2_ON_C3_S3; it forces ADC2 use on the C3/S3 path.[2]

For occasional samples while Wi-Fi is running, I would use oneshot and check the return code.[1] For a continuous stream, I would start with ADC1 and follow the ESP32-S3 guide's supported configuration.[2]

I checked ESP-IDF 6.1.[1][2] I did not test Arduino analogRead() or measure a FireBeetle on the bench.

Our FireBeetle validator ran 15 checks and flagged eight documented defects in the vendor material. It reported zero failures, and both ADC/Wi-Fi assertions passed. I did not test a physical board, so those numbers cover source consistency and copy only.

I maintain the TinkerNews FireBeetle 2 pinout page, so the link is mine.[5]

The page marks its imported entry unreviewed, while the pinout section is reviewed by hand.[5] The A5 mapping and source drawing are there.[4][5]

Sources

[1] https://docs.espressif.com/projects/esp-idf/en/stable/esp32s3/api-reference/peripherals/adc/adc_oneshot.html
> "ADC2 is also used by Wi-Fi. adc_oneshot_read() has provided protection between the Wi-Fi driver and ADC oneshot mode driver."
[2] https://docs.espressif.com/projects/esp-idf/en/stable/esp32s3/api-reference/peripherals/adc/adc_continuous.html
> "ADC2 DMA functionality is no longer supported to retrieve ADC conversion results due to hardware limitations, as unstable results have been observed."
[3] https://wiki.dfrobot.com/dfr0975
> "Supports WiFi/Bluetooth5 LE, Mesh protocols, Matter (IoT/smart home)."
[4] https://dfimg.dfrobot.com/nobody/wiki/0aa4e609926355484ad0cab49548d2f3_0x0.jpg
> "11 A5 ADC2_0 T11"
[5] https://www.tinkernews.com/boards/dfrobot-firebeetle-2-esp32-s3
> "A5=IO11/ADC2_CH0. ESP-IDF one-shot protects ADC2 access shared with Wi-Fi; continuous/DMA ADC2 is unsupported by default on S3 (force-use config exists)."

TinkerNews Podcast #59: Wireless Relay Stations, ESP32 Audio Docks, and 5 GHz FPV Video

TinkerNews — Mon, 26 Oct 2026 20:34:53 +0000

The TinkerNews podcast has a new episode: TinkerNews Podcast #59: Wireless Relay Stations, ESP32 Audio Docks, and 5 GHz FPV Video.

🎧 Listen to the episode: https://www.tinkernews.com/issues/59-wireless-relay-stations-esp32-audio-docks-and-5-ghz-fpv?utm_source=devto&utm_campaign=podcast

TinkerNews #59: Wireless Relay Stations, ESP32 Audio Docks, and 5 GHz FPV Video

TinkerNews — Mon, 26 Oct 2026 19:53:36 +0000

Originally published in TinkerNews Issue #59. Free weekly DIY electronics.

Wireless Relay Stations, ESP32 Audio Docks, and 5 GHz FPV Video

Issue 59 brings together practical builds including a two-board NRF24L01 relay station, an ESP32 networked audio dock, an ESP32-C5 analog FPV video receiver, and a custom…

⚡ Lead build: Build a Wireless Arduino Relay Control Station

Two Arduino boards share the work in this practical BlueCore build. A Mega serves as the central station, while an Uno collects sensor readings and controls relays at a distance. NRF24L01 radios carry messages both ways, with code, schematics, and wiring diagrams included for reproduction and adaptation.

Read the build → (via instructables.com)

🖨️ 3D Printing

Kiln Connects AI Assistants to 3D Printers

Kiln adds an MCP layer between compatible AI assistants and existing 3D printer services. A maker can connect OctoPrint, Moonraker, PrusaLink, or a USB printer, then inspect status, prepare jobs, start prints, and monitor progress, while keeping approval gates for files, heat, motion, and unattended operation.

Read the build → (via github.com)

⚡ Arduino

Build a Wireless Alphabet LED Wall

A familiar TV prop becomes a practical electronics lesson here. This weekend build combines a crafted alphabet panel, a multiplexed LED matrix, an Arduino, and wireless control. The available article excerpt does not name the exact board, wireless module, pins, or command method, so those details need checking before publication.

Read the build → (via instructables.com)

Simulate Traffic Signals with Arduino and Proteus

A Proteus simulation shows a multi-arm intersection changing lamp states while separate displays count down each phase. One Arduino runs the signal sequence, and a second handles MAX7219 displays through serial data. It is a useful way to test timing, communication, and display behavior before building hardware.

Read the build → (via github.com)

Building an ESP32 Audio Dock

This project puts an ESP32, network access, physical controls, and dedicated audio hardware into one dock. Its repository brings together electronics files, ESPHome configuration, factory images, and browser installation tools, giving makers a practical starting point for assembling the device and adapting its firmware to related hardware.

Read the build → (via github.com)

From Schematic to Finished Board: Arduino PCB in KiCad

A blank KiCad project becomes a fabricated Arduino-compatible board through schematic capture, footprint selection, routing, checking, and manufacturing files. The build shows how an ATtiny3226, USB-C power and data, UPDI programming, regulation, headers, and familiar software support can fit into a custom board design.

Read the build → (via community.element14.com)

Move Your Arduino Prototype to a Custom PCB

Loose jumper wires are often the first sign that a working Arduino project needs a better home. This guide compares an Uno shield, a module carrier, and a standalone ATmega328P board, then covers schematic capture, power, programming, layout, and fabrication checks for a reliable custom build.

Read the build → (via pcbeditor.com)

Build an Arduino Ultrasonic Distance Meter

Reflected sound gives an Arduino a simple way to measure distance. This project pairs an HC-SR04-style ultrasonic sensor with basic timing code, wiring, and a calculated reading. It also shows where results can vary, so makers can test calibration before using the circuit in robots, alarms, or level sensors.

Read the build → (via researchgate.net)

🔧 DIY Electronics

Build a Simple Milliohmmeter

Ordinary meters often miss the resistance in short wires and joints. This build applies a known current, measures the resulting voltage, and calculates resistance with Ohm’s law. Regulator ICs, a digital voltmeter, and four wire sensing make a useful teaching tool, though accuracy depends on contacts, wiring, resolution, and calibration.

Read the build → (via eleccircuit.com)

Pico.Lab: Raspberry Pi Pico USB Web Multitool

Cramped benches make full sized test equipment awkward, while many compact instruments cost too much or rely on command lines. Pico.Lab uses an ordinary Raspberry Pi Pico, a USB hosted browser interface, and an analog front end to handle quick checks, while leaving demanding measurements to dedicated lab equipment.

Read the build → (via hackaday.io)

Build an ESP32-S3 E-Reader Mainboard

Silkscreen provides the electronics for a pocket e-reader without hiding the design from builders. Its ESP32-S3, e-paper connector, battery charging, microSD storage, and physical buttons form a useful starting point. Production files simplify ordering, but Silkscreen firmware is not publicly available yet, so check software status first.

Read the build → (via github.com)

📶 ESP32

An ESP32-S3 Board Connects Vending Machines to Cashless Services

Inside a narrow four-layer PCB, an ESP32-S3 links a vending machine’s isolated MDB bus with Wi-Fi, cashless services, telemetry, sensors, and switched outputs. A remote antenna, protected power input, and modular connectors address practical installation problems, while the accompanying software connects the board to mobile and self-hosted services.

Read the build → (via pcbway.com)

ESP32-C5 Receives 5 GHz Analog FPV Video

A small ESP32-C5 board now receives 5 GHz analog FPV video through software-defined radio processing. C5VRX demodulates the FM signal and feeds a simple resistor-ladder DAC. Its low-cost hardware makes a useful receiver possible, but latency, sensitivity, range, and video quality still need testing for real FPV flying.

Read the build → (via hackaday.com)

🌐 IoT

A Proximity Interlock for Machine Safety

A MAX32630FTHR based prototype watches for people near moving machinery, then links detection to an alarm and shutdown response. The schematic shows how sensing, control logic, indicators, and the machine interface work together, while the project also makes clear why certified industrial safety hardware needs more safeguards.

Read the build → (via electronicsforu.com)

Build Offline Sound Awareness Aid with Arduino UNO Q

For people who cannot rely on hearing, AudioSense offers a practical starting point: a microphone, MAX9814 amplifier, Arduino UNO Q, and local sound classification. The prototype aims to identify important environmental sounds and provide awareness alerts without sending captured audio to an online service.

Read the build → (via electronicsforu.com)

🍓 Raspberry Pi

Small Boards, Big Builds: Raspberry Pi Zero Projects

A tiny Linux board can run far more than a desktop experiment. This project roundup gathers Raspberry Pi Zero builds for portable, wearable, networked, gaming, and discreet applications, with the Pi Zero W adding wireless access. Each linked tutorial provides its own wiring, Python code, and construction details.

Read the build → (via circuitdigest.com)

🔩 Recommended reads

ESP32 Snake Game with MPU6050 and OLED

Embedded Nerd's motion-controlled build: MPU6050, OLED and a complete Arduino sketch. The tutorial we picked for this swap, wired end to end.

Read the build → (via embeddednerd.com)

Tindie Blog

What makers actually sell: new gear, seller stories and open hardware news.

Read the build → (via blog.tindie.com)

Circuit Cellar

Embedded design articles from the magazine that has covered microcontrollers since 1988.

Read the build → (via circuitcellar.com)

🔩 From the bench

Wire gauge (AWG) chart

One of 15 free no-signup bench tools for the projects in this issue.

Read the build →

TinkerNews is a free weekly newsletter with the best DIY electronics builds:
ESP32, Arduino, Raspberry Pi, IoT, robotics and 3D printing.
Subscribe free → https://www.tinkernews.com

Reading SMD resistor codes without guessing

TinkerNews — Sat, 24 Oct 2026 11:09:17 +0000

A 0603 resistor falls off the tweezers and lands face up, and the marking is
472. That is either 4.7k or 47k depending on which digit your eye decides is
the multiplier. Two minutes later you have measured the wrong one and the divider
is off by a factor of ten.

The codes are arithmetic, except when they are not. Three systems cover almost
everything on a hobby bench, and each fails in its own way.

The three digit code

Three digits: the first two are the value, the third is how many zeros to add.

472 is 47 followed by two zeros: 4,700 ohms, 4.7k.
103 is 10 followed by three zeros: 10,000 ohms, 10k.
221 is 220 ohms.
100 is 10 ohms, because zero zeros is a real answer.

This is the most common marking on cheap parts, and it is usually a 5 percent
part.

The four digit code

Four digits, same idea with three significant figures: 1002 is 100 followed by
two zeros, 10k. 4991 is 4.99k. You see this on 1 percent parts, which is the
first reason to care which system you are reading.

Letter notation for values under 100 ohms

When there is no room for a multiplier that makes sense, the letter takes the
decimal point's place.

4R7 is 4.7 ohms.
R47 is 0.47 ohms.
0R0 is a zero ohm link, which is a jumper wearing a resistor costume.

The EIA-96 code, and why it looks wrong

The one that catches people is a two digit code plus a letter on a 1 percent
0603: 01C, 68X, 30B.

Here the digits are not the value. They are an index into a 96 entry table, and
the letter is a decade multiplier:

A is times 1, B times 10, C times 100, D times 1,000.
Below A the multipliers go fractional: X is 0.1, Y is 0.01, Z is 0.001.

So 01C is the table value for 01, which is 100, times 100: 10,000 ohms.

If you try to read 01C as arithmetic you get nonsense, because there is no
arithmetic to do. That is the whole trick, and it is why "just multiply the
digits" advice produces a divider that reads 0.01 ohms and a very confused
evening.

Checking by measurement, which still matters

A meter beats a code, but only if you read it honestly:

In circuit, expect low. A resistor in parallel with anything reads below its own value. If 10k reads 6.8k, the part is probably fine and you are measuring its neighbours.
Below 1 ohm, subtract the leads. Probe resistance is a real number, and on a 0.47 ohm part it is a large fraction of the reading.
A code with no marking at all is a real state: some manufacturers omit it on small packages. Measure, then mark the drawer yourself.
Tolerance covers the rest. A 222 on a 5 percent part may read 209 ohms and still be in spec, which is why replacing parts on a meter reading alone throws away good components.

The tool

I keep a free code reader at tinkernews.com/tools/smd-resistor-code-calculator
that handles all three systems, including the EIA-96 table, and shows the nearest
standard E24 or E96 value when the code you typed is not a part you can buy.
Disclosure: I built it, and it is free with no signup.

The arithmetic is also in a small library at
github.com/tinkernews/electronics-tools
if you would rather call it from a script than open a page.

TinkerNews Podcast #58: MatTris, MirrorBallBot, and the ESP32 Science Tricorder

TinkerNews — Mon, 19 Oct 2026 19:53:54 +0000

The TinkerNews podcast has a new episode: TinkerNews Podcast #58: MatTris, MirrorBallBot, and the ESP32 Science Tricorder.

🎧 Listen to the episode: https://www.tinkernews.com/issues/58-mattris-mirrorballbot-and-the-esp32-science-tricorder?utm_source=devto&utm_campaign=podcast

TinkerNews #58: MatTris, MirrorBallBot, and the ESP32 Science Tricorder

TinkerNews — Mon, 19 Oct 2026 19:46:47 +0000

Originally published in TinkerNews Issue #58 — free weekly DIY electronics.

MatTris, MirrorBallBot, and the ESP32 Science Tricorder

Issue 58 brings hands-on builds spanning a pocket Arduino arcade, a Raspberry Pi robot balancing on a ball, and an open-source ESP32 science tricorder—plus practical projects for…

🌐 Lead build: Build an ESP32 SHT41 Temperature and Humidity Monitor

An ESP32 and SHT41 form a compact environmental monitor with simple four wire I2C connections. The Arduino IDE can send readings to the Serial Monitor or an OLED. With factory calibration, useful accuracy, low power needs, and SHT4x compatibility, this build provides a practical base for larger IoT projects.

Read the build → (via randomnerdtutorials.com)

🖨️ 3D Printing

M3-CRETE: A Meter Scale Paste Printing Reference

M3-CRETE gives qualified teams a documented starting point for meter scale cementitious paste printing. It covers mechanical design, low voltage interfaces, configuration, and BOM information, while leaving high risk electrical work, material validation, safety engineering, and construction compliance to each builder and their own controlled facility.

Read the build → (via github.com)

⚡ Arduino

Self Contained PIR Trigger for Halloween Props

A small 9V module gives Halloween animatronics a portable motion trigger. An HC-SR501 senses movement, while a PC817 optocoupler separates that sensor circuit from the prop control wiring. A custom two part enclosure protects the electronics, holds the battery hardware, and keeps the assembly easy to place.

Read the build → (via blog.adafruit.com)

Pocket Tetris Arcade with Arduino and LED Matrix

A familiar block game becomes a real tabletop object in MatTris Arcade. An Arduino-compatible controller runs the game, an LED matrix shows the playfield, and physical buttons handle play. The 21-step build follows the enclosure, wiring, assembly, programming, and testing needed to make the console feel complete.

Read the build → (via instructables.com)

🔧 DIY Electronics

Build a Knock Activated Monster Box

A tiny knock becomes a surprisingly expressive Halloween reaction. This child friendly box uses an electret microphone, a one transistor amplifier, an Arduino, and a servo to sense sound and move a monster. Its schematic and construction notes also teach biasing, AC coupling, threshold detection, and servo control through one playful build.

Read the build → (via build-electronic-circuits.com)

OnePage: Build an ESP32 C61 E Reader

OnePage turns an ESP32 C61 board into the center of a complete DIY e reader project. Its repository connects electronics, firmware, enclosure files, a board SDK, and browser tools, giving makers a practical way to inspect, source, fabricate, assemble, and adapt a wireless handheld reading device.

Read the build → (via github.com)

Building a PYNQ-Z2 Mixed-Signal Oscilloscope

A custom PCB turns the PYNQ-Z2 into an open measurement platform with a dual channel, 16 bit oscilloscope, logic analyzer connection, and arbitrary waveform generator. FPGA logic handles acquisition and processing, while ngscopeclient provides a desktop view. The repository also documents planned AI integration, though implementation details remain limited.

Read the build → (via pcbway.com)

RP1 Opens the Full Humanoid Robot Stack

RP1 treats a humanoid robot as a reproducible system, not a sealed demonstration. Its repository connects structure, joints, electronics, firmware, control, and learning tools, while publishing CAD, schematics, PCB layouts, Gerbers, BOM data, and assembly notes for builders with serious fabrication and robotics experience.

Read the build → (via github.com)

OnePage: Build an ESP32 C61 E Reader

Read the build → (via github.com)

📶 ESP32

Give an Arduino Wired Ethernet with ENC28J60

Getting a low-cost ENC28J60 board working with an Arduino Nano takes more than connecting an Ethernet cable. SPI wiring, chip-select settings, library choice, and voltage checks all matter. Once configured, the small controller can join a LAN for web pages or data exchange, though ESP32 users need different pins and software.

Read the build → (via tweaking4all.com)

Build 16 Expandable GPIO Channels for ESP32

Running short on ESP32 pins is common when a project adds relays, buttons, sensors, and indicators. This compact MCP23017 board moves those signals onto I²C, provides 16 terminal connections, and supports eight addressable modules. Reverse polarity protection, 5 V regulation, and clear address LEDs keep the hardware practical.

Read the build → (via elektormagazine.com)

Connect a Zehnder ComfoAir Q to Home Assistant

An ESP32 and CAN transceiver give a Zehnder ComfoAir Q a practical link to Home Assistant. This ESPHome project carries ventilation data and airflow commands from the unit’s CAN bus to the ESPHome API, with board choices, wiring guides, power notes, and OTA updates included.

Read the build → (via github.com)

Building an Open Source ESP32 Science Tricorder

This handheld cyberdeck packs an ESP32, custom sensor boards, a microspectrometer, a magnetometer, and a Python interface into a 3D printed enclosure. Its open repository includes firmware, PCB layouts, print files, assembly guidance, and design history, giving makers a practical reference for building portable scientific instruments.

Read the build → (via github.com)

🌐 IoT

This ESP32 Bin Tracks Fill Levels and Collection Routes

Fixed collection schedules send crews to bins that may be empty while busy locations overflow. This project uses an HC-SR04, ESP32, Wi-Fi, MQTT, and a dashboard to measure fill levels, report alerts, and suggest collection routes. It offers a clear, practical IoT example for campuses, canteens, and municipal services.

Read the build → (via projectech.in)

ESPHome Bridge Reads JK-BMS Data

Battery packs often contain useful data that stays trapped inside the BMS. This ESPHome component places an ESP32 between a JK-BMS and Home Assistant, using UART-TTL or BLE to decode pack and cell readings. It adds dashboards, alerts, and automations without replacing the battery system’s safety functions.

Read the build → (via github.com)

Build a Wi-Fi to Ethernet ESP32 Router

An ESP32 with a W5500 Ethernet interface can share an existing Wi-Fi connection with wired devices. This project provides a separate LAN, DHCP, NAT, routed mode, and optional WireGuard protection. It suits home labs, isolated IoT testing, and devices that cannot join enterprise Wi-Fi directly.

Read the build → (via github.com)

Turning a CYD into a Wireless Security Toolkit

A $7 ESP32 Cheap Yellow Display can become a handheld wireless security tester with HaleHound CYD firmware. Its touchscreen groups more than 40 modules in one interface, while browser flashing keeps setup simple. Some functions need extra radios, so check the hardware notes before building and testing in an authorized lab.

Read the build → (via github.com)

Building an ESP32 Audio Bridge for Beolab Speakers

Vintage Beolab speakers need a quieter signal than a PCM5102A normally provides. This ESP32-S3 bridge handles TV and network audio with careful attenuation, 32-bit processing, source trims, startup muting, and practical fault finding. Its lessons cover Ethernet timing, PCB footprints, power cleanup, and diagnosing audio task underruns.

Read the build → (via hackaday.io)

ESP32 Field Camera Meets Reality

A low-cost camera node can capture images on a workbench, yet field use exposes weak links. This build connects an ESP32-S3, OV5640, Android phone, Flutter app, and cloud AI, then examines communication, image quality, app boundaries, and code maintenance.

Read the build → (via note.com)

🍓 Raspberry Pi

13 Games on a $5 Raspberry Pi Pico 2

A breadboard, a small color display, physical switches, and a speaker turn a roughly $5 Raspberry Pi Pico 2 into a playable 13 game arcade. Pico2Arcade uses the RP2350 to handle graphics, controls, sound, and game timing at a claimed 60 frames per second. Its open source code and build notes are on GitHub.

Read the build → (via icode.com)

A Raspberry Pi Robot That Balances on a Ball

MirrorBallBot replaces wheels with one spherical contact point, using motorized rollers to keep its body upright and moving. A custom Raspberry Pi HAT connects the electronics, while camera feedback and Python software guide corrections. Demonstrations include finger following, disturbance recovery, and travel along predefined paths.

Read the build → (via instructables.com)

Run a Local AI Assistant on Raspberry Pi

ZeroClaw provides a Rust-based, self-hosted agent runtime for Raspberry Pi projects. It can connect natural-language requests with software tools and interfaces such as GPIO, I2C, SPI, and USB. This is a software foundation, not a finished robot, so wiring, model setup, permissions, and safety rules remain your responsibility.

Read the build → (via github.com)

🤖 Robotics

Build a PID Line Following Robot

At the front of this small robot, several IR sensors read the floor while two motors make constant steering corrections. The project links sensing, position estimates, feedback code, motor control, calibration, and mechanical design in one machine that immediately shows whether each part is working.

Read the build → (via gra.ge)

Arduino PT100 and PT1000 PID Controller PCB

Stable temperature control starts with good feedback. TSRCT-PCB-01 pairs an Arduino Nano Every with PT100 and PT1000 inputs, PID firmware, and two 5 V SSR outputs. The KiCad board provides a practical base for experimental heaters, while details such as calibration, display hardware, and temperature range need confirmation.

Read the build → (via pcbway.com)

🔩 Recommended reads

ESP32 Snake Game with MPU6050 and OLED

Embedded Nerd's motion-controlled build: MPU6050, OLED and a complete Arduino sketch. The tutorial we picked for this swap, wired end to end.

Read the build → (via embeddednerd.com)

Tindie Blog

What makers actually sell: new gear, seller stories and open hardware news.

Read the build → (via blog.tindie.com)

Circuit Cellar

Embedded design articles from the magazine that has covered microcontrollers since 1988.

Read the build → (via circuitcellar.com)

🔩 From the bench

Voltage drop and wire gauge

One of 15 free no-signup bench tools for the projects in this issue.

Read the build →

TinkerNews is a free weekly newsletter with the best DIY electronics builds:
ESP32, Arduino, Raspberry Pi, IoT, robotics and 3D printing.
Subscribe free → https://www.tinkernews.com

How to pick the right wire gauge for a low voltage project

TinkerNews — Thu, 15 Oct 2026 10:39:44 +0000

Thin wire is the quiet killer of DIY projects. The build works on the bench, then the LED strip dims at the far end, the motor stalls under load, or a connector gets warm for no obvious reason. Nothing is broken. The wire is just too thin for the current it carries over that distance.

Here is the whole decision, in the order it actually matters.

The two rules that matter

Voltage drop, not wire temperature. People pick wire gauge by the ampacity chart, which is a fire-safety number for mains wiring in a wall. On a 5 V or 12 V project, the failure you actually hit is drop: the resistance of the run eats the volts before they arrive. A 5 V LED strip on a 5 m run of thin wire can arrive with 3.9 V and visibly dim.

The 3% rule. Keep the total drop, out and back, under 3% of the supply. For 5 V that is 0.15 V. For 12 V it is 0.36 V. Below that, and most electronics behaves like it does on the bench.

The math, once

Copper has a resistance per metre that depends only on its cross section:

drop = 2 × length × current × resistance_per_metre

The 2 is there because current travels out along one conductor and back along the other. Both halves drop volts, and both count.

A worked example: 5 A over 5 m of 18 AWG.

18 AWG is 0.021 ohms per metre
drop = 2 × 5 m × 5 A × 0.021 = 1.05 V

On a 12 V rail that is 8.8% and clearly too much. Moving to 14 AWG (0.0083 ohms per metre) gives 0.42 V, about 3.5%, close enough that the next size up removes all doubt.

Gauge, current and distance, together

The useful way to hold this in your head is that every three gauge steps roughly halves the resistance. So a run that is twice as long needs about three sizes thicker for the same drop. That is also why long runs surprise people: doubling the distance is not a 2x problem in practice, it is a step change in what wire you need.

Practical bands for low voltage projects:

Small signals and sensor runs: 22 to 26 AWG is fine, drop is irrelevant at milliamps.
Short runs of a few amps (LED strips, small servos): 18 to 20 AWG.
A metre or two at 5 to 10 A: 16 AWG at minimum.
Anything longer, or anything that a motor starts and stalls on: 14 AWG and up, and think about where the power enters the strip.

The traps that bite

Daisy chaining power into an LED strip. The wire between segments carries the current of every segment after it. Feed the strip from both ends, or inject power every few metres, and the last pixel stops being a dimmer cousin of the first.

Connectors, not wire. A cheap barrel jack or a Dupont run can add more resistance than two metres of decent cable. If a joint is warm, that is where the loss is. The paper amp rating is a starting point, not a guarantee.

Battery projects. The wire from cell to regulator is often the thinnest part of the build and the one carrying the highest current. Shorten it before you thicken it, and keep the ground return in mind: the drop is in both legs.

Grounding on mixed-voltage builds. A shared ground that has visible drop between two boards turns into signals that read wrong, not just power that sags.

Do the sum for the exact build

Rules of thumb get you close. For a specific rail and length, put the real numbers in and read the answer: the voltage drop and wire gauge calculator takes the volts, the one-way length, the current and the gauge, and returns the drop in volts and percent, the 3% check, and the smallest gauge that passes. Every result is a link, with the inputs in the query string, so you can send the exact scenario to whoever is wiring it.

Free, no signup, no ads. It is one of the bench tools we keep for the builds we write about weekly at TinkerNews.