There is some theory that claims you can repel mosquitos and other insects with ultrasonic sound waves, and has been quite a contentious issue for many years - dating back to the original kit from Dick Smith Electronics years ago. However it's always interesting to see new attempts, and one of these has been demonstrated by Instructables member "DangerousTim".
His device is based around a minimal Arduino-compatible circuit which has a simple transistor amplifier that drives the round piezo elements you can see in the image below. These can act as speakers and thus generate the ultrasonic sound waves.
If you have an insect problem, this may be the solution - so for more information, visit the repeller's Instructable page. And for more, we're on facebook, twitter and Google+, so follow us for news and product updates as well.
If you're wanting to make your own Arduino-compatible project such as the repeller above, you'll need an ATmega328P MCU with Arduino Uno bootloader:
This is the same Atmel AVR ATmega328P microcontroller used in the official Arduino Uno, as well as our Eleven, EtherTen, USBDroid, and other boards. Perfect for building your own Arduino-compatible project directly on a breadboard or on a custom PCB, or for replacing the MCU in an existing board. Comes with the Arduino Uno bootloader pre-installed. Better still, it even has a special label stuck on top with details of the pinout, so you don't even need to look up the datasheet when connecting it up in your project! For more information and to order, click here!