Temperature measurements with an NTC thermistor

Following a discussion on Facebook I put here an online tool to calculate the output of a voltage divider consisting of a fixed resistor and an NTC thermistor following a first order Steinhart–Hart equation. The calculations are based on a voltage divider where either the voltage over the NTC or over the pass resistor is… Continue reading Temperature measurements with an NTC thermistor

Top deal of the week?

Unschlagbares Angebot der Firma Elektor.

Today I received a newsletter from the publisher Elektor. I am offered a special deal on a Peltier power generator which can power an LED light from a small candle. And this for an astonishing price of €99.95 instead of the normal price of €119.95. I’ll have to buy this – or wait a second…… Continue reading Top deal of the week?

Nerd or not?

Today there was a geocaching event celebrating Nerd Day. I must admit that I wasn’t aware of the significance of today’s date, but I also knew that I can probably be considered being a nerd. In the early days of the internet, while still writing my master’s thesis in Kiel, I already scored high on… Continue reading Nerd or not?

The end of a short story in life…

This afternoon the birdsnest outside my office window has been plundered by a crow or raven. Even though the parent-birds got reinforcement by two other fieldfares they never had a chance. The small birds only had a few days of life but they somehow enriched my days.

Hatching time

Ten days Mrs Fieldfare has been sitting in her nest – today was the big day: until late afternoon three eggs had hatched. Now also Mr Fieldfare has to show some effort who has not been much around the nest lately. This is the first day in the life of the young fieldfares in time… Continue reading Hatching time

BirdCam v4

Touch down!

It took four attempts to finally get a suitable webcam to observe the bird’s nest outside my office window. Most cheap webcams, even those which show off with true 720p HD resolution simply cannot cope with the different outdoor lighting conditions over a full day. After a lot of testing and research on the net,… Continue reading BirdCam v4

Setting up webcam exposure under linux

I had some problems with fswebcam to set the automatic exposure. The exact way how to enter certain parameters is not clear from the lacking documentation, but it works fine if you set parameters through another command line tool. This is the script behind BirdCam: #!/bin/bash DATE=$(date +"%Y-%m-%d_%H%M") v4l2-ctl -c exposure_auto=1 v4l2-ctl -c gamma=5 v4l2-ctl… Continue reading Setting up webcam exposure under linux