Getting started with WSGI and Python as well as uwsgi application server
20 mins
A simple summary of hat WSGI can do for one, how to use it with Python and how to run the uwsgi application server (and how to solve the deployment problem there) from the viewpoint of someone who already developed web applications in many different languages and frameworks.
Using the FY6900 with an external USB to serial bridge
6 mins
Short article about circumventing the CH340 contained in the FY6900 function generator by using its external 3.3V serial interface and an CP2102 or any microcontroller.
Detecting frequency, delay and phase relation as well as multiple targets using correlation functions
15 mins
A short story about how one can use autocorrelation and cross-correlation functions on discretized samples of radio frequency data and also noise to detect the frequency of a single signal, the delay of a reflected signal, the phase relation between two signals and how one can track multiple reflective targets in applications like LIDAR, sonar or radar using correlations - and how to get them robust against external influence.
Heterodyne, Superheterodyne, Homodyne and Lock-In Amplifier
14 mins
A mini introduction about the terms heterodyne, superheterodyne, homodyne and lock-in amplifier
Simple time lapse with ffmpeg
4 mins
Short summary on how to generate time lapse videos from webcams or other sources using ffmpeg on various platforms
Simple laser cutting and engraving capabilities for a 3D printer with a 450nm diode laser
27 mins
This article summarizes some experiments using a simple 450nm laser diode on a 3D printer for some basic laser cutting and engraving in paper, plywood and other simple to cut materials.
Why you should not use SMR disks for ZFS
12 mins
A short story about SMR disks in ZFS ZPools and why you should never ever use them there even when it looks ok on the first look and why you should replace them as fast as possible even when you don't see problems in the beginning.
Switched mode DC-DC converter basics
40 mins
A short summary of the basic principles behind switched mode DC-DC converters (buck, boost, buck-boost, etc.), maximum power point tracking and impedance matching as well as a short recapitulation of the charging and discharging of reactive elements such as inductors and capacitors.
A simple digitally controlled small current source
11 mins
Simple project that provides a digitally controllable linear current source up to 500 mA powered from a rectified 230V to 12V transformer. The whole current source is bias-able to high voltage (-2 kV in this case) by opto isolating it's serial communication path
Simple 230V monitoring using PC817 opto coupler
3 mins
A really simple circuit to monitor the presence of a 230V AC line using an PC817 opto coupler and a 5V or 3.3V microcontroller
