Good starting place to learn about metal detection systems - Page 1
Forum section: electronics / beginners

author: Infraviolet
author_rank: Super Contributor
timestamp: September 16, 2021, 07:28:05 pm
content: I'm interested in building a screw detector as part of a larger project, and want to learn as much useful new stuff along the way as feasible. My interest is in making it as small as possible and detecting fairly small screws, but only at close range. I have looked online for circuit exmaples but don't want to just copy, I want to learn some stuff along the way. I have several years of general electronics and embedded programming experience, and have made a variety of analogue and digital projects before, usually custom sensor systems interfacing in to microcontrollers and on custom board designs. Could anyone advise of a good place to start looking so I can put myself on a path towards developing such a system? Again I'm not after answers, but introductions so I can have the satisfaction of working out answers for myself.Thank you

author: Manul
author_rank: Super Contributor
timestamp: September 16, 2021, 09:14:19 pm
content: Through my experience related to metal detectors (I design and build them as a hobby), I never found good comprehensive sources on the subject (like books, or web pages). Maybe there is, but I just don't know. There are some information available if you search more specific topics, like for example how to build a high performance search coil, ways of implementing ground balancing, etc. So what I suggest is to assemble your knowledge methodically and step by step. First search what kind of technologies are used today or were used historically. For example induction balance, pulse induction, etc. Then narrow your search about one specific technology, see articles, schematics, patents. Narrow the search even more and learn specific topics.You will get general idea relatively quickly. In the end it boils down to circuit design. This subject is as wide as the electronics itself. While trying to design a good metal detector you will easily burry yourself into noise and stability problems, filters, thermal EMF effects, digital signal processing and who knows what else. But these are general electronics topics.By the way, there is such thing as induction proximity sensors, which might be good for your application. It would be much more time efficient and robust solution if you could use something of the shelf.

author: kripton2035
author_rank: Super Contributor
timestamp: September 16, 2021, 09:54:55 pm
content: https://www.geotech1.com/cgi-bin/pages/common/index.pl?page=metdet&file=projects.dat

author: ledtester
author_rank: Super Contributor
timestamp: September 19, 2021, 01:43:56 pm
content: DiodeGoneWild just recently posted a series of videos on metal detectors.The first one analyzes how a cheap $2 kit works. He then goes on to present his own design.- Building a metal detector & how does it workhttps://youtu.be/Bs9U15qQo0E- DIY DD metal detector 1 - first successhttps://youtu.be/eCRgNr6jj2g- DIY DD metal detector 2 - coin at 35cm, audio indicator, PCBhttps://youtu.be/-czOV-hKSlA

author: Infraviolet
author_rank: Super Contributor
timestamp: September 28, 2021, 11:19:00 pm
content: Thanks for the links

author: Francedetection
author_rank: Newbie
timestamp: November 16, 2024, 09:30:50 am
content: Hello!Thanks a lot for this article! I learned some very interresting things about this subject to help me on my daily tasks of the moments..Btw I'm new on this forum and excuse my French I'm from Lille in France!Have a good week!

author: Solder_Junkie
author_rank: Frequent Contributor
timestamp: November 16, 2024, 10:47:23 am
content: For my metal detecting activities, I have used a Garrett Pro-Pointer for years, they pick up small pieces of metal and are probably the style of detector you are looking to make. I don't know what method of detection they use, I would guess pulse induction, but not sure.https://garrett.com/sport/pro-pointerSJ