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Brain Surgery with the CH32V003

I crack open a punchy little toy, show how the original just squishes two contacts to light the eye LEDs off a pair of LR41s, then perform some brain surgery to cram in a tiny lithium cell and my own board that triggers lights—and an incredibly annoying tune—on each punch. It sips about 7 µA in deep sleep and wakes via a yellow trigger wire, but the soldering was fiddly and full of swearing. Tape it up, cram it back in the head, and yes, it works a treat… maybe too well, because the beeping is driving me mad.
24 October 2025

10¢ MCU Music Hack - CH32V003

I spun some tiny WCH boards at PCBWay around an 8‑pin MCU (48 MHz, 16k flash, 2k RAM) to beep tunes off a coin cell. I tried hand-soldering, then used my paste-dispensing PCB printer—expired paste still worked great. Standby sips under 8 µA, but it locks out programming; a WLink flash wipe rescued me. Wake draws ~3.3 mA, and audio peaks hit ~130 mA (~13–14 mA average), which browned out the coin cell. A tiny 80 mAh LiPo with a TP4056 (modded to ~100 mA) proved the design, then swapping the buzzer’s base resistor from 1k to 10k tamed it...
24 October 2025

ESP32 PDM Microphone - What do you do with the L/R pin?

I treated myself to some hands-free probes and dug into the PDM mic on my ESP32 board. I was confused that the new I2S PDM API only asks for clock and data—no LRCLK—yet the mic datasheet shows an LR/SEL pin. The trick: in PDM, LR is just a static select. Tie it low and data is valid on the rising edge; tie it high and it’s valid on the falling edge, so two mics can share the same I2S lines by picking opposite polarities. I proved it on the scope and realized I don’t need to burn a GPIO on...
24 October 2025

ESP32-S3 USB UAC Audio Device - does it work?

Time for an audio project: I took my PCBWay ESP32‑S3 board for a spin—fixed the common anode/cathode LED mix‑up, verified the IMU and battery charger, then tested an I2S PDM mic and tiny speaker with a Web Serial Audio Studio (scope, spectrogram, tuner). I also turned it into a USB UAC device in ESP‑IDF: the mic is clean, but speaker over UAC is crackly (Mac/Windows toggle oddity); direct I2S WAV playback is perfect, so the hardware passes QA.
24 October 2025

High Voltage Coin Cell - 27V Joule Thief

How much voltage can we squeeze out of a CR2025? Turns out… plenty! I built a little Joule-thief-style boost circuit with two 1 mH inductors, an NPN, a Schottky, a 27 V zener clamp, and a storage cap to zap my LCD pad clean at around 27 V. I profiled it with a Nordic power monitor: about 11 mA during the boost and ~9.28 mC per click—so tens of thousands of presses from one coin cell. Then I added a second transistor tied to the zener to auto-limit the drive, dropping hold current to about 1.5 mA—huge win. Scoped it...
24 October 2025

Super Easy ESP32-S3 Dev Board

Making an ESP32-S3 dev board is way easier than it looks. I simplify the datasheet reference: skip the external crystal, wire native USB D+/D− (pins 19/20) straight to a USB-C with 5.1k CC pulldowns, add a BOOT switch and an EN RC reset, and power it with an LD117 LDO that’s happy with ceramic caps. In KiCad I build the schematic with Espressif libraries, add LEDs for 5V, 3V3, and a blink GPIO, set up net classes, route a clean USB differential pair, stitch a solid ground plane, and label everything. It’s a bit wide—just gang breadboards together—and you end...
24 October 2025

Dodgy Circuit Defused - fixing the silly red thing.

I’ve got all the bits to bring this little arcade game back to life: swapped the dead 3.3V regulator (had to buy 100… oops), tried and successfully revived the totally flat Li‑ion with a trusty charger board, and I’m adding a couple of Schottky diodes to handle USB vs battery power. Used the mini hot plate to reflow the regulator (not my finest soldering and, of course, the microscope didn’t record), confirmed 5V in and 3.3V out, and the screen actually boots. Next up: stick the charger board down with Kapton, wire B+/B− to the test points, cut the right...
24 October 2025

Dodgy circuit could have caused a fire!

So, I got this red mini handheld game thing from AliExpress and it died pretty quickly. After a bit of tinkering, I found that it still draws current but isn't turning on because of a dead battery and a burnt voltage regulator. I removed the faulty components and injected 3.3 volts directly into the system, and guess what? The screen lights up and it works, but there's no sound. Despite the hiccup with my microscope, which stopped recording some interesting bits, you get the picture. It's partly revived but not quite there yet. Big shout out to PCB way who...
24 October 2025

Forget the Arduino Serial Plotter - try this instead!

Hey everyone! So, you're probably familiar with the Arduino serial plotter, right? It's useful for basic stuff, but I wanted something better, more cross-platform, and runs right in the browser. Enter the web serial plotter, using the web serial API! It's super flexible with zoom, export options, and light/dark mode. You can even pan through history or switch to absolute time. Plus, it's all secure and runs locally. It's open source, and I'd love your contributions or bug reports on GitHub. It's still a work in progress, but I think you'll find it pretty handy!
24 October 2025

Tearing Down a Bistable Cholesteric Display

So, I finally tried out this bistable cholesteric display from my AliExpress stash after seeing Big Clive's teardown. It's super cool to play with, and I mean, it just clears up with a button press after you scribble on it. Gave it a whirl to understand the voltage involved and even ended up sparking it with some reverse polarity action (not the smartest move, I know). I might've broken it, but hey, it still sort of works manually. Check out Big Clive for a deeper dive into its reverse engineering, and remember to like and subscribe!
24 October 2025

This brings back happy memories

Join me as I dive into the nostalgic sounds of dial-up internet, exploring how these iconic tones played a role in the history of digital communication. We'll decode the melodies that once connected us to the world, with insights and analysis that bring the era of dial-up back to life.
24 October 2025

This Number Does Nothing… when you have native USB

This video's all about how the baud rate setting on an ESP32S3 with native USB does absolutely nothing. Testing with different baud rates showed no effect on performance; every rate worked flawlessly. With USB full speed, you can expect data transfers of up to 7 megabits per second. So, baud rate? Totally irrelevant with native USB—it's full steam ahead, folks! Grab my test code from GitHub, give it a go, and share your results in the comments. If that blew your mind, don't forget to like and subscribe for more ESP32 insights!
24 October 2025

I Made a Digital Twin for my PCB - IMU Visualiser

Hey everyone! In this video, I’m diving into testing the cool functionality of my new board that I designed, and demonstrating how to use both an accelerometer and gyroscope with my favorite little tool. The board is rocking an LSM 6DS3 sensor, which works like a charm, despite the tiny LED snafu from before (watch my 'ninja repair' in the previous video, haha). I walk through the different modes, including a fusion mode that magically blends sensor data for accuracy. Also, there's some cool 3D modeling in play where you can bring any model to life on my public website...
24 October 2025

Nice fix - what do you think?

In this video, I attempt to fix my previous PCB mishap where I mistook a common anode RGB LED for a common cathode. This required some soldering surgery with a hot plate, flux, and soldering iron. I maneuvered a pre-shaped enamel wire to complete the circuit properly and avoid previous mistakes. Despite a minor mishap with too much solder resist, the repair was ultimately successful, and the LED works beautifully now!
24 October 2025

Oops I Did It Again… Swapped VCC and GND, on My PCB 🙈

Hey everyone! In this video, I made a little snafu with my PCB layout by confusing a common anode with a common cathode for my RGB LED. I walked through fixing it by a bit of desoldering, applying solder resist, and reconnecting with a fine wire. Thanks to PCB Way for their awesome service, and as always, all the mistakes you see are mine alone! It's all sorted now, and our LED is shining brightly once again. Let's take a look at the process!
24 October 2025

Crowd Funding Success? I must be rich!

Hey guys! So, I wrapped up my ZX Spectrum crowdfunding project, and boy, it was quite a ride! The campaign went gangbusters with 146% funding, and I shipped everything out. Total revenue was £12,839.57, but after costs, I pocketed a neat £4,273.91—though, spoiler, that's before considering my labor! There was quite a learning curve understanding COGS, pricing strategies, and the hidden costs of hardware projects. It took about 13 months from idea to fulfillment, and I amassed 436 hours of work! I discussed vital strategies like working with distributors and how PCBs' cost plummets with bulk orders. Plus, the unknowns,...
24 October 2025

World’s Smallest USB-C Li-Ion Charger?!

I found some super compact USB-C lithium battery chargers on AliExpress, and they're tiny! The PCB is just 10mm by 6mm, but it packs a punch with a linear lithium-ion battery charger chip, LP 4054. It's equipped with indicator LEDs for charging status and includes essential resistors and capacitors. Be cautious, though, as it can get warm during use. I've decided to recreate this neat design in Keycad, showing you each step, paying tribute to our Patreons and PCB Way along the way. Let's see how the design translates and if it passes all checks!
24 October 2025

Surprisingly not CR*P - Vibing hardware

Well folks, what an adventure! After vibe coding our vibing button, I took up the challenge to vibe code the actual hardware for an ESP32 S3 dev board. Used a tool called at pile and gave it a whirl with some AI help from Claude. Interestingly, it handled everything from sourcing components with LCSC part numbers to wiring them up. Had a wee hiccup with missing capacitor in the RC circuit, but overall it was a thrilling ride watching the AI process! A bit of tweaking here and there, and we're good to go! Can't wait to see it in...
24 October 2025

A Vibe Coded One-Button Mechanical Keyboard - ESP32-S3 USB+BTLE

Hey folks! So, I've been tinkering with a compact PCB featuring an ESP32 S3 Mini, and it's been a blast! This little guy has a USB-C and battery connection, with nifty chips like a charge controller and voltage regulator. I'm diving into mechanical keyboards with some cherry switches, and guess what? I made this cool 'Vibe button' for a single key keyboard! I even used AI to vibe code it, so it sends command-enter when pressed. PCB Way did a stellar job on the assembly, and now I'm setting up the RGB LED for charging status. Let's make coding more...
24 October 2025

Blinkety Blink #electronics #arduino #arduinoproject

This video is a mesmerizing musical journey that captivates the audience with its enchanting tunes and harmonious melodies. It's all about appreciating the beauty of music.
24 October 2025

Flying sparks #electronics

Just playing around with some high-voltage experiments for fun!
24 October 2025
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