Air quality driven ventilator

Many modern homes have mechanical ventilation, with a 3 position switch to control the speed. However, common ventilators allow stepless speed control. They set the speed corresponding the voltage of an input connector. If 0V is provided, the fan goes off, if it is +10V, the fan goes to maximum speed. If only there was a way to set a voltage between 0V and +10V wirelessly, by a popular home automation protocol such as Z-Wave.

Actually, there is. It is a brilliant device by Qubino, called the Flush Dimmer 0-10V. I installed it into our ventilation unit (a Stork CMFe), and connected it to my Z-Wave network and Domoticz.

Qubino 0-10V Flush Dimmer inside Stork CMFe

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Disposable code

I have often been in situations where we decided to reuse existing code. Business people seem to think that reusing existing code is free. After all, this is the promise that paradigms like OO promised us. But in reality, retrofitting code for a new usage often proved nearly as costly, or even more so than if we had started from scratch. This is not necessarily a bad thing. Having a component with multiple uses makes sure it is well tested, and that all consumers benefit from maintenance and improvements.

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Automatic Christmas Tree

Our home is running Domoticz and a Z-Wave network. Using these, I added a simple LUA script to turn the Christmas tree on and off automatically, depending on motion in the living room. To be precise, motion would turn it on immediately, and 10 minutes after motion stopped, it would turn off again. T...

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Debat tussen Richard Dawkins en Lawrence Krauss

Lawrence Krauss en Richard Dawkins

Op zaterdag 21 oktober was er een debat met Richard Dawkins en Lawrence Krauss, georganiseerd door Brainwash. Hieronder volgt een beknopte samenvatting.

Niet het begin van de vorige eeuw, maar de periode 1955-1975 was een baanbrekende periode voor de wetenschap. Is dat niet jammer voor Nederland...

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Decentralized Social Web

Sharing between offline computers

We create content all day. We take pictures, write comments on articles, or even the articles themselves. We save bookmarks, or press some like or heart buttons. Even if this content is of no value to anyone else, at least it is to ourselves. Still, we trust other parties, commercial ones, with servers often in other countries, to give us back our content any time of the day with the click of a button. Even if they want to, they may not always be able to do so. In my previous post I wrote that we put too much trust in the internet.

Would it not be nice if all this content was on our own computer hardware, that we could easily categorize and search it, and share copies with our friends? I would like to share some ideas that I have to make this technically possible, so this is going to be a technical article for that reason.

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