Thursday, April 4, 2013

Do-It-Yourself Metal Detectors (Part 3)

 (The "guts" of an old metal detector. Image courtesy Geotech Detectors.)

In this post Arizona gold miner G.T. Blocker will provide additional information and personal views on do-it-yourself (DIY) metal detectors. There's additional perspective to be gained here, so I urge you to read on.

More on DIY Metal Detectors (G.T. Blocker):

Why in the world would I want to build my own metal detector?

"Metal detectors are designed for very specific tasks. A detector that is great at finding coins is all but worthless at finding small pieces of native gold and on it goes. Some of the benefits of a 'home-grown' detector are:"

"1) Self satisfaction. You built it, it's your machine, and it does what YOU want it to do."

"2) It can be less expensive than a commercial detector for a very specific capability or need (small nuggets, treasure troves, artifacts, etc.)."

Gold Concentrators
Metal Detectors
"3) You will TRULY understand what your detector is doing, it's limitations, and how to get the most from it."

"4) Bare circuit boards (and sometimes kits) for quality machines are available. So no 'designing it yourself' is required."

"5) If it breaks you can fix it...even in the field (you did build it didn't you?)."

I've never built anything electronic. How hard is it for a beginner?

"From your first kiss to that first 'smile' of gold in your pan, nothing is easy for the beginner...sorry to say. However, learning to solder is a LOT easier than that first kiss. If you have never soldered an electronic component before, purchase an inexpensive kit with some blinking lights or something  similar (~$10). Get that right and you're good to go." 

Won't building my own metal detector require a ton of expensive gear?

"Nope. You will need to invest in a basic 'lab,' however. While those with greater means might go for an 'uber lab,' I suggest a basic setup with an oscilloscope (though this is not absolutely necessary). The oscilloscope will be the most expensive piece of gear in your lab but well worth it." 


That's great. So what is a basic 'lab' and what does it cost?

"A basic electronics lab consists of a well-lighted and clear working area of about 4 feet by 2 feet for your equipment and projects. At a minimum you'll need the following:"
  • "25-watt soldering iron and stand"
  • "Capacitance/inductance meter"
  • "Digital multimeter (DVM)"
"I also strongly suggest the following:"
  • "Signal generator (easy to build with 1, 2, and 3 above)"
  • "Oscilloscope (I can't stress this piece of equipment enough)"
  • "Frequency meter"
"Your mileage may vary, but that's the gist of it."

What does it cost?

"That's up to you. You can buy retail or look for new or used deals on Craig's List, eBay, etc. Above all, you'll need to do your own homework in this regard."

So there you go. I want to thank G.T. for his willingness to share this info with the rest of us.

Best of luck to all of you out there...

If you liked this post, you may want to read: "Do-It-Yourself Metal Detectors (Part 2)"

 (c)  Jim Rocha (J.R.)  2013

Questions? E-mail me at


  1. All my life if I wanted something I would try to make it first before buying it. I've gotten pretty good at it to.As part of my liveing,I make gun holsters and horse saddles. I've made sluice boxes out of old road signs for myself and friends that work really great.I've made most of my prospecting gear,and all of my horse gear,but Electronic anything.....well.....I'm surprized I even figgured out how to use this computer enough to write this!!

  2. With anything you make yourself, there comes a huge amount of satifaction and pride when it works. Tyeing fishing flys or reloading bullets are just a few examples....who can't aford a fish fly? If you could pull this off, and find a big nugget or an old coin,what a thrill it would be! Heck, I can't even get the batteries into the store bought ones right the first try....

    1. It's not just the machine, it's the user as well. Nugget shooting is an art and not everyone is good at it...I'm definitely not one of the experts when it comes to that. Best, J.R.

  3. We are all good at some things Gary...but not all! J.R.