To connect a 12V relay to the Arduino you need the following things: – 1 Arduino – 1 diode for example 1N4007 – 1 NPN transistor for example 2N2222 (in the US) or BC548 (in Europe) – 1 relay for example one with coil voltage 12V and switching voltage 125VAC/10 A – 1 multimeter Step […]
Connecting a 12V relay to Arduino Continue Reading
Being a broke amateur photographer isn’t easy. Film, chemicals and paper aren’t cheap and a budget for some studio lights is non existant. So, I decided to, with the help of my trusty arduino, create my own sync controller to use with disposable camera flash circuits. By using a photoresistor the arduino can sense when the flash from your
Arduino Flash Controller for Photography Continue Reading
I’m currently helping a couple of engineering students finish a senior project that didn’t get finished last year. Long story… Anyway, it’s a bicycle brake tester being built for Paul Components. The mechanical design is great, but they had trouble with the electronics. Part of those electronics involved writing numbers to a pair of Sparkfun
Driving multiple Sparkfun 7-segment displays with an Arduino Continue Reading
After a bad water damage (our cellar basically filled up whilst we were away for several days), I decided to monitor our water usage for anomalies. Enters Arduino… The idea of this project is to use an arduino to count every drop of water that goes through the water company meter. Said arduino needs to
Aquameterduino: Water meter plus Arduino Continue Reading
Thanks to Will Greiman’s Fat16 library for the Arduino, I finally got a useful version of this datalogger working! Here’s the schematic: And here’s the code. The code is highly configurable: it can save raw A/D values or converted values, it allows software-defined gain, it can collect for a set time or until user input,
Arduino datalogging accelerometer with µ-SD storage Continue Reading
This tutorial will show you how to make a thermal cycler from scratch for about $85. In short, PCR (polymerase chain reaction) amplifies bits of DNA, creating millions of copies of a target sequence. You can use it to test a DNA sample for a specific gene, for instance, to check for genetic modification in
Arduino PCR (thermal cycler) for under $85 Continue Reading
I got my start in microcontrollers with the Arduino, as many of us outside of electrical engineering did. (And still do!) The ease of programming that little board makes it a great gateway… and like any gateway, sometimes you go through. Most of my projects now don’t use Arduinos directly. For simple microcontroller applications, it’s
ISP Clip for ATtiny44/84 (or others!) Continue Reading
The RFI-DJ is a USB device for playing MP3 files from your computer. You have a set of RFID cards, each one with a song name written on it. You choose a card and place it on the RFI-DJ, and your computer will play that song. Its magic! Actually, it’s not magic. It uses an
RFI-DJ: MP3 Playing RFID Thing Continue Reading
My students need to learn LabVIEW —I know, it’s proprietary software, and expensive, but until a viable open-source equivalent comes along we’re stuck with it— and one of the exercises I have them do is to make a program to analyze radioactive decay. This gives them experience in using counters, plotting data in real time,
Radioactive isotope decay simulation Continue Reading
Hi! In this tutorial you will learn to make a mood lamp with Arduino. I know that you may have seen a lot of mood lamp projects with Arduino, but I wasn’t very satisfied with them because they all change the color very abruptly. So, I decided to make a smooth mood lamp and I
Make A Mood Lamp with Arduino Continue Reading
