New Prototype Detector - My First Analog Attempt

[Sun-Boy]

Hi Folks,

Well...life, work, and health happened and I had to put the detector on hold, but I'm getting back to it.  I got new boards and components on order, as well as a few mechanical parts.

I'm sticking to the all analog design for now, but have a recently retired embedded programmer friend whose interested in helping out, my programming skills are basic at best.

I'll update the thread as I progress through the design.

-S

[Erik Oostra]

On 1/30/2021 at 1:47 PM, Sun-Boy said:

About the 60KHz, I came to that frequency through testing, I tested my system with multiple frequencies and found that gold worked best right at 60KHz , and that iron, silver, nickle, etc., worked well with either low or high frequencies - and if the detector can't see gold, well, it really has to find gold .

I really like your thread and detector, it'll be interesting to see how it performs in the wild..

As mentioned above 60kHz is great for tiny shallow gold, you even show this in your photo where your detector picks up a thin gold chain with a little cross.. But this is in your workshop, on a beach this sort of chain can be very hard to find, even with beach detectors like the Equinox (40kHz) or Deus 2 (45kHz)..

On my beaches these detectors are hard to run on high single frequencies and I normally run them in multi frequency programs.. To find small gold jewellery I've also used my mate's Gold Monster (single frequency - 45kHz) which just tolerates dry salty sand but freaks out on the wet stuff, it also can't handle black sand.. I've had more luck in these situations with my Gold Bug Pro (single frequency - 19kHz).. 

Have you considered lowering the frequency on your detector so it can be used in the wild? I think that you'll have more luck running at a lower frequency, say 15kHz which in my mind is at the higher end of the 'general purpose' frequencies and will still hit on small gold jewellery.. A lower frequency is also better if you want to get any real depth out of your detector, this will also increase your finds (good and bad) in the wild.. 

I guess it'll come down to how the beast behaves in a workshop versus the wild.. 

It's a very interesting project and I'll be keeping an eye on your thread for updates.. Thanks for showing us the fruits of your labour..   

 

[Sun-Boy]

Hi Erik,

Thanks for the input, reducing the frequency to 15kHz won't be a problem, running dual frequency is also an option, the original system I worked on eons ago was running at 3kHz.  This revision is pretty well set unless I cut up the pcb, which I don't want to do right now.  I'm a builder designer and my actual in the wild detecting is limited to near nothing.  This design is based on a system I worked on many years ago, its going to be fun seeing how it performs.

I'm in South Texas, so I'm going to see if I can get some locals in San Antonio to test it out and give feedback.