An autonomous solar weather station

By martinm, in Internet of Things and Measures, october 24,2013.

Do you recall the solar box? Actually, it has never worked well enough to be useful. Here at Yoctopuce, it has been renamed the NULL box. Ruthless, but not so far from reality. But this week, we have a new version of that experiment. This time, it is much easier to make it work because we now have hardware designed with that kind of application in mind.

How to measure a NTC thermistor via USB

By mvuilleu, in Measures, september 15,2013.

Yoctopuce provide three different methods to measure temperature, but there are even more techniques. Thermistors are another option: they are a family of electrical conductors whose resistance varies in a deterministic way based on their temperature, and that can therefore be used to measure temperature. So can we get anything out of them, for instance using a Yocto-Knob?

What happens inside the fridge?

By martinm, in Measures, june 14,2013.

What exactly happens when we open and then close the fridge door? Obviously, the light switches on and off, but how do temperature and power consumption vary? To be frank, this question is not quite innocent. I started a while back to have doubts about how well, or bad, my fridge was working. I have therefore decided to get to the bottom of it. And I made some rather interesting discoveries.

Cosm alternatives to record sensor measurements

By mvuilleu, in Reviews and Measures, may 22,2013.

A few days ago, our beloved Cosm Beta service that we used to recommend for real-time graphs from your Yoctopuce sensors, has changed its usage terms. Renamed Xively, the web site is now focusing on revenue-generating services. Unfortunately, some essential features that we have been using, such as the ability to choose the display time range on a graph, have disappeared. It is therefore time to look for alternatives to Cosm...

Turn your Raspberry Pi into a network multimeter

By mvuilleu, in Measures and Tiny PC, april 26,2013.

Measuring devices which you can directly connect to the network are usually very expensive, more than 1'000 Euros. However, numerous applications, such as monitoring an experiment started on a napkin, could benefit from them if they were more affordable. We are going to show you therefore how to very easily transform a Raspberry Pi into a very flexible Ethernet multimeter, with the help of a simple Python script. A simple solution based on standard USB modules, demonstrated in a video.