In addition to the WeMos battery powered temperature server, it would be nice to know what the remaining level of the battery is, so we can recharge it in time. This is easily done using a voltage divider circuit and the analog input on the WeMos D1 mini module.

WeMos D1 mini is an ESP8266 based board that can be programmed with Arduino IDE. In this blog I will descirbe how to make a simple WiFi based server that is being powered by a Li-Po battery and shows temperature and humidity inside your browser window.

ESP8266 is Wi-Fi microchip which can be programmed just like a normal Arduino board. For that purpose some additional software needs to be installed inside the Arduino IDE.

Browsing though Aliexpress shop on 11.11, I came across a DVB-T+DAB+FM USB dongle that claimed to be modded into a SDR (Software Defined Radio). The price was under 10 euros, so I decided to give it a try. After some tryouts I managed to get it working.

Blink LED is a Hello World! application for microcontrollers. If you manage to get it running, you can assume that you are all setup and ready for further developments on your board. In this blog item I will cover how to do that on a STM32F407 Discovery board.

A while back I have assembled this bench power supply kit, which I received as a gift from my friend Eric. The kit was published in a Dutch electronics forum (Circuits online) as PCB Lab voeding. It was time to create a casing for it as it was just lying around in my drawer and was not really being used.

18650 batteries are known for it's high energy density, but this comes at a price. In order to protect the battery from overcharging or overdischarging a number of ICs need to be used. Luckily these charge and protector circuit boards are readily available for sale in all shapes and sizes. In this blog post I am going to build a charger that uses such a circuit.

MicroPython is a programming language that is derived from his big brother Python and is optimized to run on microcontrollers. In this blog we will focus how to get it running on ESP32 with a SSD1306 OLED display.

If you have watched Star Trek Voyager, then you must remember the door chime that is played when someone wants to enter a quarters. In this blog I will describe how to create such a doorbell using Arduino Nano and some extra modules.

Helping scientific research by mining Gridcoins can be satisfactory. You contribute to various projects by donating your CPU power. In return you get Gridcoins. This mining process uses energy and we want to do this in an economical manner.