Category Archives: Gadgets

Build a bunch of test wires

I found these mini test-hooks useful, I already have built some of these, but now I build some. On one end of the cable there is a hook-probe, on the other end an alligator clip. I have purchased from eBay “10pcs 15inch Double-ended Test Leads Crocodile Clip Roach Clip Jumper Wire”, and “Multi-color 10 Pcs… Read More »

How NOT to 3D design a project box

I’m working on a project, where I need a case. So I designed a box in the idea in my mind, that printing two from the same part will fit together face to face. So I have added overhangs, and groves that should meet. But in the end it turned out that they don’t fit.… Read More »

How to design a line following robot

I already have shown how I have made an Arduino controller for my old LEGO robotic kit; and also, how to recognize colors. Now I will form a cool project around these achievements, and build a line following robot. This post focus on two key parts of the build: what is the recommended hardware design… Read More »

DIY Egg Decorating Machine

Goal I have seen some egg painting machines out there, but I found them too complicated to be a DIY project. These are some kind of CNC laves. In my design the pen (aka. tool) is in your hand, so the pen movement not controlled by the machine. The machine only performs the rotation task.… Read More »

Chess clock

Preface Lately I play some chess again, and I was realized, that it will become very boring, if we do not limit the time of the game. So a chess clock is required, but instead of buying one, it seams to be a great DIY project, and we will have a hackabe clock around the… Read More »

Lego robot controller – Pin-outs

Wiring This is the pin mapping we have for the onboard components. Arduino pins This is the same, but from the other direction RF port pins 10DOF port pins Extension port pins This is the extension port pin-out. Top view. Dual color sensor extension panel Logical: Physical (top view): BPX 43 wiring  

Loudspeaker enclosure

This document is about a speaker case I was built around a TDA2030A amplifier circuit and a 130mm car speaker set. Preface The story began some years ago, when I’ve bought a TDA2030A DIY Kit as a Fater-child project to build a power amplifier together. The amplifier was build, but it turned out that we… Read More »

Rotary encoders

See video explanation of this article here: Preface Rotary encoders are pretty cool and easy way to interact with our software. However it is not straight forward to achieve trusty operation with it. The problem in the physical characteristics of these devices, that I will explain in this essay. The second most problematic thing is… Read More »

JoyStick Shield

Preface Surfing the eBay I just have seen an interresting Arduino extension board with an analog joystick, and some buttons. This model has ports for connecting other devices, like Nokia LCD screen and RF module. As I have both, and I just built a joystick myself, I decided to try this prototyping extension. The board… Read More »