Fourier Transform spectrometers vs. Grating spectrometers

Introduction This article compares some of the less obvious details of fourier transform spectrometers and classical grating spectrometers. It contains some apparently not-widely-known observations I made recently, but is probably not interesting to you if you are not into spectroscopy. This is also why I will skip explaining how the two spectrometers work. The article will first compare the two types of spectrometers in terms of signal-to-noise ratio, and then […]

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Poor Man’s Optics: $50 Fourier Transform Spectrometer

From my last electronics project, I had some leftover laser diodes. Because it would be very very sad to just have them lie around, I decided I should build something out of them. And since it’s a laser, it would be stupid to do something which doesn’t exploit the coherence properties of the light it emits, no? Thus, I attempted to build a fourier transform spectrometer. The setup is shown […]

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Homemade 10 Mbit/s Laser / optical Ethernet transceiver

Today’s network backbones don’t use copper wires any more — they use lasers to transmit information. The laser light usually propagates in a fiber, but while convenient, this isn’t strictly necessary; you can also send the laser light through the air in a collimated beam, like an ordinary laser pointer. Because this sounds cool, I thought I could build something like that. Here’s the prototype: Concept For simplicity, I decided […]

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Randa sprint wrap-up and considerations on packaging complex applications with AppImage

On Sunday, this year’s KDE sprint in Randa, Switzerland came to an end and I am now back home. It was a productive and fun week, as always when meeting the other KDE folks. I spent a lot of time on polishing things and fixing small issues mostly in KDevelop, such as: reduce flickering of the completion widget in kdevelop fix various cases where KDevelop’s navigation widget (see above) would […]

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KDevelop 5.0 standalone executable for Linux

I am currently at the KDE sprint in Randa, Switzerland. There are about 40 nice people here, working on making KDE software awesome. This year’s focus is on deploying our software more nicely — on Windows and OS X, but on Linux as well. Especially for user-faced applications like KDevelop, it really makes a big difference whether you use today’s version, or the one from two years ago. Many people […]

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kdev-python on Windows: try it!

I spent the last two or three days playing around with KDE on Windows, with the aim of getting my Python language plugin for KDevelop to run there. In the end, it wasn’t that hard to get this to work — not as hard as I would have expected it to be, anyways. Several things needed to be fixed in kdev-python, the build system required a bit of tickling, but […]

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kate / KDevelop sprint in Berlin

The last few days, we had a joint kate and KDevelop sprint in Berlin. I finally found the time to fix up the Python language support plugin for KDevelop, which was in a quite bad shape in the last few months. Most importantly, the 1.7-py3 branch now supports Python 3.4.3, and the master branch supports KF5 (this mostly thanks to Laurent, who did most of the porting) and Python 3.5, […]

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21cm HI telescope: first results

During the last days, I had the chance to record some radio astronomy data with my 1.4 GHz telescope. The receiver system is more or less unchanged compared to what I described in the last post, except that I have pretty versions of the amplifier and filter boards now: For the measurements I performed until now, I only used a small biquad antenna without parabolic reflector. The collecting area is […]

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