Stop it with the coin cells!

Hey companies making sensors and remotes! (for smart home/home automation and the likes). If you can make a sensor microscopic – fine If it needs to be portable – fine But if it is rather small, but still visible you are not doing anyone any favor by making it as small as possible with a coin cell battery that runs just a few months or even less. If your sensor can run for years and… Continue reading

Wet sensors (or humidity sensor troubles)

Intro Well there is no surprise: i went through a lot of temperature and humidity sensors. Some I already reported on, and some more i tried afterwards. And none seem to survive the exterior readout very well. The defects are mostly related to humidity, but not temperature. What happens when they fail: mostly the humidity saturates to 100%. Here is my most recently replaced one from outside, a BME280: After a while, the sensor reads… Continue reading

Fast 3D printed boxes

Intro Finding the proper box for my sensors is not easy. But even after finding one that mostly worked, I wanted to explore more sensors and still have a bit of freedom while doing that. Of course, that means 3D printing with the new 3D printer. There is just one problem …. 3D printed boxes take a long time to 3D print. An example Here is the newest sensor module I designed, which can fit… Continue reading

10002 I2C connectors

Intro In my first iteration of sensors I relied on wire connections between sensors and the actual node board. The result for a motion sensor and a temperature and humidity sensor looks like this The problem with that is that during sensor modules assembly run I spend quite a bit of time on the wiring. On top of that, the result is a mess of small wires inside a box. It makes it hard to… Continue reading

10002 Screens and controls

Intro There is no point in having a smart home if you don’t see interesting information or control things. The traditional way, ever since the concept of smart home came to be, is to have some sort of central control panel for everything. In today’s world, that would be a tablet. In my attempt to do that, I ran into the control panel horror. What else? In parallel to this, I thought about the idea… 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

Cheap China

My experiences and recommendations for cheap electronic modules from China. Continue reading