By using so called ladder diagrams one can build a PLC-program like a schematic diagram using relais like in the early days of automation.

What is it: An RF Power Meter is a device which you can use to measure the power a transmitter outputs. Why did I built it? Read all about it!

Short high current pulses can prevent or even solve sulphating of the lead accumulators and can be used to measure its state of charge

This is a universal IoT sensor interface. It will challenge you to create power efficient sensor-apps over WiFi.

Sound file player. Play sounds stored on an SD card with 2x 7W output power.

The laser plot clock writes the time on a piece of glow in the dark sticker material using a violet laser module.

Efficiency booster for candles. The peltier lamp converts heat energy released by a tea light into electric energy in order to drive a USB LED light.

Simple circuit that projects the car's speed on the wind screen using 7-segment LED displays and an Arduino Uno.

In 2010 we published a power supply called UniLab (project 090786). It was able to deliver 30 V and 3 A. This design can be considered its successor.  Maximum voltage is also 30V and the maximum output current is limited to a little over 3 A (5 A is possible, but with reservations). We used a different step down voltage regulator, the LM2677-ADJ.

Although SMPS (switch mode power supplies) can take various structures (Buck, Boost, Flyback, Forward, etc.), they are always based o

How to detect objects placed on a touch screen...

MPPT – Maximum Power Point Tracker

A few years ago Elektor published a workshop on spot welding for smaller objects (welding battery packs) using capacitive discharge. This was not a finished project, rather a starting point for experiments and development.

IntroductionA simple Platino-based battery Tester is designed for not too demanding (hobbyist) applications. A simple way of establishing the capacity of a storage battery is to recharge it and then discharge it again in a controlled manner.

At home we ripped all our audio CDs to a NAS and most of the time we use Windows Media Player or VLC player (we still don’t agree which one’s the best) in random order play to have some background music in our workshop.

Automatic license plate recognition (ALPR) is a mass surveillance method that uses optical character recognition on images to read and recognize number. They can use existing closed circuit are road-rule enforcement cameras, or ones specifically designed for the task.

A guitar input module for easy breadboarding. This project spun of from the CoCo-ri-Co guitar tuner.

Because the CoCo-ri-Co Cool Controller Concept is a hexagonal board with a powerfull ARM Cortex M0 processor and a ring of LEDs, we thought that a 6-string guitar tuner would be a nice application for it. By adding an analog front-end and some clever software the LEDs can indicate how well the guitar is tuned.

The audio traffic light is a straightforward circuit which tells you whether an audio signal is dangerous for your ears or not.

On discovering that my previous design based on a blocking oscillator and diac strobe pulser was a bit heavy on the battery, it seemed about time to attack the problem from a different angle with an oscillator that is easier to tweak for the most favourable characteristics.

Forget the Internet of Things (IoT), wearable electronics will be the next big thing. Join Intel and become a market leader too.Post your ideas and projects here as a contribution (or on a separate page). The best ideas and projects will be taken to the next level. Publish in Elektor Magazine and see Lady Gaga wear your design!