Electronics Design

Build your own metal detector

Build your own metal detector article mentions a pretty interesting Diy Arduino based metal detector. The article starts with with an explanation of how most oscillator based metal detectors work. Most metal detectors uses a search coil that act as part of an oscillator circuit. When metal is put in proximity of the search coil

Acronym definitions

The fields of electronics, computers and telecommunications is filled with acronyms. To help in surviving on this world of acronyms I started to compile in the 1990′s my own list of acronyms, and you can find my collection of acronym definitions (over 19000 definitions) at ePanorama.net acronym search. You should be able to find most

H-bridge ideas

An H-bridge is an electronic circuit that enables a voltage to be applied across a load in either direction. They are useful in many applications, especially when you need to make a DC motors to run forwards and backward. H-bridges are available as integrated circuits, or can be built from discrete components. Here are first

Reverse engineering the of a ULN2003

I have many times found ULN2003 and ULN2804 transistor arrays to be very useful components when I want to control some loads like relays, small electrical motors or light bulbs from TTL circuits. I have for example used ULN2803 for many applications where I have needed to control something with PC parallel port. The interesting

USB and ground loops

USB was originally designed for desktop use, but it is increasingly used for industrial applications. For USB to survive in those environments, it needs to be made more rugged. It means that ruggedizing USB for ground loops and using better (more protection and better locking) connectors are often needed. Ruggedize USB connections for tough environments

Shields are your friend, except when…

Shields are your friend, except when… article tells that engineers just love to put shields on circuits, mostly as a defensive measure against signals on the outside getting into and disturbing our circuits, but they also keep signals inside from getting out and this really makes the folks responsible for EMI compliance happy. Even on

Arduino cellphone

Hackaday mentioned some time ago an interesting Arduino cellphone. The fact that you can build a cellphone around an Arduino is pretty neat: An Average Joe can build this thing with a minimum or background knowledge and without breaking the bank. Wow. The components include and Arduino Uno, GPRS shield from Seeed Studios, a TFT

DC circuit breakers

Knowing the electrical characteristics of direct current and its differences in comparison with alternating current is fundamental to understand how to employ direct current. Direct current presents different problems than alternating current with a regard to the phenomena associated to the interruption of high value currents since the arc extinction results to be particularly difficult.

Lightning protection

Every summer we get thunderstorms, with the accompanying lightning in Finland. It is expected that thunderstorms starts in few days. Varo! Torstaina salamoi article says that it is expected that next Thursday there will be (according to weather forecast) 5000-10000 lightning discharge events in Finland. Lightning is a massive electrostatic discharge between electrically charged regions