Reddit:Electronics

This project is a compact evaluation PCB designed for the nPM1100 Power Management IC by Nordic Semiconductor. The board provides the essential circuitry to evaluate the core features of the PMIC in a minimal footprint while exposing all IO pins for external interfacing.

PCB dimensions: 22 mm × 16 mm PCB layers: 2 All components: Surface-mounted on the top layer Header pitch: Standard 2.54 mm (0.1")

More info on GitHub https://github.com/P-rth/LIPL-Assessment/blob/main/ProblemStatemet2%2Freadme.md

It's not finished yet, but it will be soon. Only one PCB is left once I finish that and do the wiring, it'll be done.

Although I have been messing around with PCB software for a while, I just recently built my very first PCBs and got both to work. The 1st one is the main PCB for a battle bot I made (there is supposed to be an ESP32 in the middle, but I removed it to show what is under). The 2nd one is its controller.

Could be used as a part of an alarm system. Its a 555 timer in astable mode driving the TRIAC's gate at around 2Hz, powered by a capacitive dropper to be able to run directly from mains without a separate PSU.

This is a WLED ESP32 project that was a lot of fun. Custom clear acrylic rods sanded all 4 sides for diffusion and diffraction.

Strips are Muzata 12vdc 3-led modules per pixel addressable RGB.

I’m just running at 25% brightness, these get crazy bright.

Seems no video allowed in post, pics are not enough.

Visit r/WLED and see cool projects other Redditors did. Some are seriously talented.

Every thing is safe and a fuse. Power is through a GFCI outdoor wall outlet, so no zappy. PSU and strip are IP67.

Box is 6 x 6 x 4 “ and weather proof.

I can control everything over Wifi, and have it turn on at sunset with longitude and latitude.

Honestly just wanted to share this! I've done tons and tons of soldering, but have never made a protoboard of any kind.

Gave it a shot and damn, came out alright!

For those wondering, its a 4 axis stepper board for a lil' robot I'm working on.

Playing songs on it is very interesting

Hi all, what is resister R54 rated to?

I know that sounds silly, but I’m colourblind and I can’t see what colours are there!

Any help would be greatly appreciated :)

Two channel I2C level-shifting interface with a lot of safety components (our products got a lotta ATEX conditions to meet) for the firmware engineers to wield. Not pretty, but it needed doing QUICK.

Rushed it so all but the hologram part of my features don't work. Doesn't matter since THE HOLOGRAM PART WORKS. Based largely on the andotrope invented by mike ando which is based largerly on the zoetrope. However I made a couple of my own modifications to achieve a see through display.

I did open source it: https://github.com/very-high-priest/Andotrope

https://x.com/theapache64/status/1949763814351843547

If you have on old and/or faulty dehumidifier, rip the fan out of it. They are quite small and have quite a powerful airflow. Just add a filter to it and you have a perfect little fune extractor. It’s a bit loud though.

For now it’s just a led and a resistor. Anode is soldered to the resistor.

I made a binary seven-segment wristwatch. Each segment represents a binary multiplier: segment B is 1, C is 2, D is 4, and so on.

Project info

Yep, I’ve used 1970’s to 1980’s era parts from Japan and Taiwan only. The whole thing is built around a mitsubishi jungle IC. The controller is external though. I have no way of testing it because analog TV was shut down a long time ago here in Czech Republic. Just built it out of love and compassion for RF circuits.

Fun fact: I’ve spent 6 hours just soldering all the components into their respective holes. There isn’t a single hole unused on that perfboard.

Hey everyone! I’d like to share a fun and useful project I recently built: a PI-controlled soldering iron system based on a Hakko handle, designed specifically for heat insert pressing into 3D prints.

You can enjoy this project from a few different angles:

1. A DIY Tool That Actually Works I originally bought a so-called "digital soldering iron" to make a heat press, but it turned out to be fake—it just used open-loop power control with a 7-segment display. No temperature sensor, no feedback, no reliability. So I decided to build my own closed-loop system using proper RTD feedback, MOSFET switching, and a real PI controller running on an STM32. Now it gives stable heat control, perfect for insert work.
2. A Showcase for My Snapboard Platform This project is also a working demo of Snapboard, my modular prototyping platform for embedded hardware. It’s like a LEGO base for breakout boards—strong and swappable, yet reusable across multiple projects. The potentiometer, OLED display, and power modules all snap into place cleanly with perfboard support. It’s been rock solid for building functional prototypes.
3. A Control-Theory Driven Design Instead of trial-and-error tuning or just using bang-bang control like most DIY temp controllers, I took a full control engineering approach:

• Collected step response data
• Fitted it to a first-order model
• Designed the PI gains using pole placement, not guesswork
• Analyzed performance metrics like settling time, overshoot, etc.

You can get a ready-to-go PI controller without hand-tuning. I even wrote a short doc on the theory and design [Notion link here].

What You See:

• OLED display shows SP, PV, and OP
• Potentiometer sets the temperature
• Serial data logging for step response capture
• Clean 12 V/24 V DC input with a switching regulator
• RTD temperature sensing and MOSFET power control