If you live with your family, a significant other or a few roommates, and you’re looking for a fun prank to drive them nuts, Connor Nishijima has the perfect trick for you: an Arduino cricket. Unlike actual crickets that are relatively consistent with the sounds they make, this one is a far cry from that. Instead, the Maker’s project will chirp for a brief second, and then go into a deep sleep for a random amount of time between three minutes and three hours. As you could imagine, this can make the source of the noise extremely difficult to pinpoint!
Nishijima combined the JeeLib library for reducing current consumption and his new library for 8-bit volume control to bring the insanely annoying “cricket” to life using nothing more than a speaker, a 7800mAh USB battery, and an Arduino. The best part? He estimates that the setup has enough juice to last for months, if not years. In his case, he enclosed the electronics within a box along with some magnets, then placed it in his vent to mess with his buddy.
For the lowest current comsumption with minimal effort, I’ll be using a 16MHz Arduino Pro Micro with a few power-hog components like the power LED desoldered. Unfortunately, the PWM speeds needed for my Volume lib only work well at 16MHz so far, so using 8MHz to conserve power is out.
However, the awesome battery calculator at Oregon Embedded tells me that at 16mA “awake” current and 200uA “asleep” current (being asleep more than 95% of the time) this should last more than three years. Of course, the battery itself will have some drain involed with it’s circuitry, but even a FOURTH of the estimated battery life still puts us at almost a full year which is good enough for me, and bad enough for my friend.
Those wishing to give this prank a try can check out Nishijima’s videos below, as well as his code on GitHub.