All about electronics and circuit design

Universal identification is futile

Bruce Schneier blog post Anonymity and the Internet has interesting points on Internet security. I can agree many of them. Universal identification is portrayed by some as the holy grail of Internet security and that anonymity is bad. According to the blog this is not the case. The problem is that universal identification won’t work.

Open Source Symbian

When Nokia bought Symbian in 2008, nobody had any reason to believe their thoughts were anywhere near Open Source. Parts of the Symbian platform have been Open Source for quite some time and other portions have slowly been released. Symbian, maker of the the world’s most popular mobile operating system, has just completed the transition

Text message ripoff

Everyone knows that movie popcorn is one of the biggest ripoffs, right? It turns out that movie popcorn carries a 600 percent markup. The biggest ripoff: text message beats movie popcorn article tells that the text messaging has a much bigger markup. Text messages themselves, are just tiny blips of data being transferred to and

Extremely simple stepper driver circuit

The normal way to drive a stepper motor is to use switched-dc voltages to energize the stepper motor coils one by one after each other. But a stepper motor will run off ac lines if you introduce a 90° phase shift between the voltages applied to the motor’s two windings. The extremely simple circuit in

Modern sound and light controlling

A Sound/Show Control Guy’s Take On the grandMA2 blog posting tells about MA Lighting grandMA2 system. The article describes a very modern control system for audio, lighting and many other things needed to run a show. Interesting text and lots of pictures. A funny thing in the keyboard is that instead of ENTER key there

Sensible web site design

The original idea of http/html was to make it easier to share information between academics, especially report. The idea on the web was that the information is presented in the way that it can be viewed in many ways and using many different devices. On the old days there were both text based and graphical

Lego router and PC

Luke’s Weblog shows how LEGO blocks can be used to build the case for a WRT54GL wireless router and a PC. Lot’s of normal LEGO blocks and lots of work is needed to build those projects. The postings are is filled with goof pictures and videos how those fun projects were built.

My FAQs have new home here

I have maintained three FAQ lists for many years. Those FAQs are VGA to workstation monitor FAQ, sfnet.harrastus.audio+video usein kysytyt kysymykset (FAQ) and sfnet.harrastus.elektroniikka usein kysytyt kysymykset. VGA to workstation monitor FAQ tells how to interface different RGB monitors to to PC VGA output and a little bit about connecting other RGB signal sources than

Differential video amplifiers

Differential amplifier approach uses an operational Amplifier. Operational Amplifiers only amplify the difference between the two input lines. This method eliminates common mode noise between the incoming signals by making A-B=C, as only the difference between A & B are amplified. Operational amplifiers is maintain wide bandwidth signals throughout your system while eliminating ground loop