Build your own metal detector article mentions a pretty interesting Diy Arduino based metal detector. The article starts with with an explanation of how most oscillator based metal detectors work. Most metal detectors uses a search coil that act as part of an oscillator circuit. When metal is put in proximity of the search coil the frequency of the oscillations change. This circuit design starts with an oscillator that produces a signal of about 160 kHz which is constantly measured by the Arduino.
When metal enters the coil it alters the frequency, which is immediately picked up by the Arduino. So in this design the traditional BFO approach is replaced with a microcontroller that can measure the frequency changes very accurately. When the ‘NULL SW.’ button is held the current frequency is stored and changes to it are are detected. This is an interesting idea to build a metal detector.
The source code is pretty compact. It promises that it works with search coil oscillator that has frequency in 20-200kHz range. This looks something that could be adapted to many different kind of search coils and maybe also for some other sensing applications.
7 Comments
Kiera says:
Fantastic goods from you, man. I’ve understand your stuff previous to and
you’re just too great. I really like what you have acquired
here, really like wha you are stating and the way in which
you say it. You make it entertaining and you sill take care of to keep
it wise. I cant wait to read much more from you.
This is actually a great web site.
Feel free to surf to my web page: doppelwandiger Edelstahlschornstein (Kiera)
Tomi Engdahl says:
DIY Metal Detector
http://hackaday.com/2013/09/28/diy-metal-detector/
Looking for a light project to teach young hackers some very basic electronics? Here’s a quick and easy weekend project, a simple metal detector!
We all know 555 timers are very useful and pop up in a wide range of projects, but did you know a metal detector is one of them?
If you don’t have a 555 on hand (tisk tisk) but still want to have some treasure hunting fun you can also build one based on an Arduino.
Martha says:
Good post. I learn something totally new and challenging on blogs I stumbleupon everyday.
It will always be helpful to read articles from other writers and use something
from other websites.
My web-site: Best Price Halloween Costumes For Teenagers On Line (Martha)
Tomi Engdahl says:
BASIC CIRCUITRY of
METAL DETECTION
http://www.talkingelectronics.com/projects/200TrCcts/MetalDetectors/MetalDetectors-1.html
Tomi Engdahl says:
EEVblog #714 – Metal Detector Reverse Engineering
https://www.youtube.com/watch?v=RqB93K47Phg
How does a metal detector work?
Dave teardown and reverse engineers the circuit in a $17 Harbour Freight wand type metal detector, and also explains how to do basic reverse engineering of a PCB.
Tomi Engdahl says:
Simple but powerful metal detector
https://www.eeweb.com/profile/calimero22/articles/simple-but-powerful-metal-detector?utm_source=newsletter&utm_campaign=link&utm_medium=EEWebEngInsp-20200213
It’s very simple to implement a valid metal detector with good performances. Very often people lose their metal objects at the beach or in the countryside. Coins, rings and necklaces disappear when they touch the ground. Starting from today this will no longer happen: thanks to this very useful device, it will be very easy to find buried items.
Tomi Engdahl says:
DIY METAL DETECTOR, Gone Wrong and Right!!
https://www.youtube.com/watch?v=yzrVHEB02Hw
By: Mehdi Sadaghdar
0:00 Wrong Way of Detecting Metal
1:48 Theory Behind How Metals Effect Inductance
6:10 More Fake and Real Metal Detector Video Tutorials
7:32 Designing a “Simple” Metal Detector Circuit
15:48 Testing the DIY Metal Detector Circuit