Steel detectors generally is a nice supply of enjoyable, and sometimes even discovered wealth. They permit the detection of steel objects at a distance, enabling hidden treasures to be found. They’re additionally extremely important to the work of minesweepers and unexploded ordnance disposal groups. [Andrius] wanted to add such a device to his kit when motorcycling through the woods of Lithuania, and thus decided to undertake a build of his own.
The detector is a completely fashionable one – followers of the 555 might need to look away now. A Collpits oscillator, constructed from two transistors, is used to generate a frequency that’s handed by way of the detection coil. This frequency is measured by an Arduino that plots a graph of the obtained frequency on an OLED show. Because the coil is handed close to steel objects, the oscillator frequency modifications, and that is seen on the frequency plot on-screen.
Not solely is it a fast and simple construct that’s achievable from what at the moment are junkdraw parts, it’s additionally one that might be readily usable by the hearing-impaired, too. It’s an ideal undertaking to sort out in case you’re seeking to familiarize yourself with primary oscillators, frequency measurement, or simply microcontroller programming usually.
Nonetheless want extra inspiration? We’ve seen a similar concept executed before.