GPP-4323 power supply review

Intro I spent quite a bit of time trying to design a digitally controlled power supply. I even have some prototypes and three articles, Part 1, Part 2 and Part 3. One day it hit me: across the years, I built multiple prototypes, spent a lot of time on it and never ended up anywhere. Why? because I did not really need one and I did not have any pressure to build one. So this… Continue reading

New 3D printer

Intro My first 3D printer was a Prusa i3 clone, which I got as a kit, installed and made some changes to reduce noise. It proven to be full of problems. I could never print ABS with it, there were consistent extrusion problems. The glass bed and glue for adhesion took a while to get going, was time consuming and dirty. Some of the 3D printed extruder parts were constantly failing and I had to… Continue reading

10002 Control panel horror

Intro I have been making some slow progress with my smart home project. I have completed a small assembly run of motion sensors, there are plenty of things that are working and I shifted some focus on making a control panel. What I normally want is a control interface that works well from both a PC and a phone. Bonus if it can look nice on a tablet to have one real control panel on… Continue reading

The coolness of RGB LEDs

Intro Ahhhh LEDs….don’t we love them? Today there is a huge variety of them. But there is one type I particularly like. These 5 mm RGB diffused LEDs, easily available from various sources and quite cheap (, aliexpress, ebay etc). Here’s why I like them They are super bright. According to some datasheet which may or may not be what you are buying from less reputable sources, the green LED peaks at 5000 mcd at… Continue reading

10002 Short assembly run

Brief progress It is quite clear that my smart home project is going quite slow. It is not that I spent a lot a time on it, but that I have been pretty busy with other life things. But it is moving again now. Motion sensors assembly Once I settled on the type of motion sensor and case, I designed some sensor PCBs . I made a small assembly run of eight sensors just to… Continue reading

Wine lamp

Intro My old Ikea GRÖNÖ lamp was long due for an upgrade to LED, but I wanted to use a strip not just buy a bulb. That is because I wanted the light controllable through my 1000² home automation system. Now, the cool thing about building my own dimmers is that I could dim the light down to very low duty factors, which is pretty good considering the way human eye responds to light levels. As a… Continue reading

Vorpal hexapod

I wanted to have a hexapod robot for a long while now. It just never seemed to be that much of a priority to spend the time or money to build one. Luckily this changed when I found Vorpal. They are selling complete kits or you can build one yourself from the plans that are provided. I was missing only a few servos and the 3D printed pieces, so I quickly decided to build one.… Continue reading

10002 Motion sensors?

Motion sensor madness Picking the right one for my smart home project is not trivial. From left to right – Osram Nightlux, Ikea Molgan, Ebay sensors with sensitivity and timing adjusment (BISS001), smaller ebay sensor with no adjustment, another ebay sensor. As you can see I have looked at 2 different options: use a ready made sensor and fit it with a radio, or build my own. Ikea Molgan I hacked one a while ago –… Continue reading

10002 Temperature sensors?

Intro There is no doubt, that integrated temperature and humidity sensors are the way to go at the moment for my smart home project. I had quite a bit of look at a wide range of sensors and settled for the SI7021. Silabs has a bigger family – most likely the same chip binned on precision – so here are cheaper options to use if I ever want to go for an application that can do with… Continue reading