Tag: DIY

TōGō-Lab now on Matrix

I’m happy to share that the TōGō-Lab Matrix server is now up and running and officially open for productive use. This is a self-hosted Matrix instance, dedicated to discussions around my hardware projects. It hope, it will gives you and me an open and privacy-respecting way to chat, collaborate, and exchange ideas.

Public Lobby

The main entry point is the public lobby, where everyone can join and get oriented: From there, invitations to project-specific rooms are handled. All project rooms are end-to-end encrypted (the lobby itself is intentionally open).

Why I made this

Idea is to bundle Discussions around ToGo-Lab hardware projects, design ideas, experiments, and implementation details. This space complements Git repositories and the blog as an additional communication channel. If you’re interested in a specific project (as referenced here on the blog or on Git), feel free to drop by the lobby and start a conversation with me.

Alternative / public Matrix presence

In addition to this self-hosted, project-dedicated server, there is also a public space on matrix.org. This is mainly for broader, non-project-specific exchanges. Same idea, feel free and show up in the TGONet-Lobby.

If you’re already using [Matrix](https://en.wikipedia.org/wiki/Matrix_(protocol) (Element, Fractal, or some another client), just jump in, so we can talk.

Hope to see you there soon.

togo-lab MATRIX Lobby_round

PC817 Optocoupler Tester – Lazy Sunday Afternoon Project

For some upcoming projects, I’ll use the PC817 optocoupler family. But sadly, you don’t always get what you think you’ve bought. So how can you simply check if they work as described in the datasheet? I wanted a quick way to verify parts before building them in.

This small tester consists of two independent circuits, runs on 5 V, and does two simple things:

  1. Quick Test – Push the switch, and if the LED lights, the optocoupler basically works.
OptoCoupler_CheckCircuit_QuickManual
  1. Frequency Test – Based on the circuit from the datasheet. Input impedance is 50 Ω, and the output can be pulled up with 100 Ω, 1 kΩ, or 10 kΩ to see how the device behaves at different frequencies.
OptoCoupler_CheckCircuit_ParameterCheck

Simple stripboard:

0002-PC817-Series-PhotoCoupler-Tester_SB

That’s it.
It’s not meant to be fancy—just a tiny 2-hour project to get reliable data and a feel for how different PC817 batches respond.
The project data will be on Gitea – ToGo-Lab, Project ID 0002,

As working proof, some simple scope screenshots:

If you’re into optocouplers or small test circuits, feel free to build along or suggest tweaks.
Always happy to hear what others find useful in their own setups. 🙂

“Hello World” Project for Tōgō Lab: FireFly Morse Blinker

This is my first hardware project on the new ToGo-Lab.io server.

Some years ago, when I started with AVR/ATTiny programming, I built a tiny Morse “throwie”: one ATtiny, one LED, one resistor, and power-friendly firmware. The goal was to use as few parts as possible to keep it cheap, while still adding a couple of useful functions.

Two main functions: Detect daylight. If it’s bright, sleep; if it’s dark, send a Morse message. The LED doubles as a light sensor.

This is a good restart for my new project home, https://togo-lab.io/, the HW version of a “Hello World” program. So I don’t plan heavy hardware work here, though I may add a small solar cell to stretch battery life. This version adds a supercapacitor and small solar cells and uses the LED as a light detector, so it only blinks in the dark. It’s no longer a throwie, more of a pendant. Hang it where it gets daylight and stays dry. It charges by day and blinks by night.

Yes – I want also a PCB and maybe you will the final result as a little DIY Project on e.g. – Tindie.

But real goal is to define the specs and a simple, repeatable workflow from Idea to real DIY Kit especially for bigger future projects.

This post will evolve as the project advances. I’ll append notes, design decisions, and lessons learned rather than writing a single post-mortem at the end. But don’t expect too much progress too quickly; this is a side hustle. Perhaps in a few years, after I retire, it will become one of my main activities.

What it is

  • DIY-Kit goal: beginner-friendly soldering kit with clear docs and hackable programm (using Arduino IDE).
  • MCU: ATtiny45/85, through-hole.
  • Power: 3–5 V, with solar + supercap option.
  • Behavior: Morse message presets, LED as light sensor for night-only blink.

Process and tooling

Roadmap

  • v0.1: Proto: breadboard + first PCB, single message, speed presets.
  • v1.0: Pilot: build guide, BOM with alternates, pilot of 10 units.
  • v1.1: docs polish, optional brightness setting, minor PCB tweaks.
  • v2.0: Zero Series
  • …

How this post will evolve
I’ll update this page with:

  • Schematics, Circuit description,
  • PCB Design, CAD. All you need to build one,
  • Build photos and assembly hints.,
  • BOM changes and sourcing notes,
  • Additional Blog post about the program itself and how to do with Arduino IDE.

Want to get involved?
Suggestions welcome. Open an issue on the repo or email tgohle@togo-lab.io. If you build one, share photos and your timing results—those will feed back into the docs and the next revision.

Schematics, Circuit description,
tbd