Build a different metal detector

[James]

I was wondering if anyone on the planet has ever made this detector work. The article came from Popular Electronics February 1969. My father constructed the machine to a exact copy an never could make it work. Many engineers tried to make if work but no one I know of has ever been successful. Stay safe an healthy. Best to all Jim

[6666]

https://www.americanradiohistory.com...op-1969-02.pdf

[Sean_Goddard]

I wouldnt bother as I doubt the septh wouldbe much beyone an inch or two on a coin.

[dbanner]

Inch or two good for pinpointer?

[Carl-NC]

This project uses an orthogonal coil, no way you would ever get a pinpointer out of it. I've never tried this circuit, but the coil design is interesting. Note that if you eliminate one of the RX coils, make the coils a lot bigger, and space them 1 meter apart you have a 2-box locator.

[James]

Interest take on the design Carl, the problem was it would not oscillate at 2 KHZ or anyother frequency. I believe that there was not enough feedback to cause it to be unstable an oscillate. Thanks for the comments, stay safe an well. Jim

[profesor]

https://www.americanradiohistory.com...op-1969-02.pdf

link does not open, is there any other link?

[Qiaozhi]

link does not open, is there any other link?

It opens ok for me.

[6666]

works for me

[profesor]

Thank you. Can you add it to the forum? I could not open it.

works for me

[Qiaozhi]

Thank you. Can you add it to the forum? I could not open it.

I've sent it to you by email, as it's too large to upload to the forum.

[profesor]

I've sent it to you by email, as it's too large to upload to the forum.

thank you. I would be very pleased.
email: [email protected].

[Qiaozhi]

thank you. I would be very pleased.
email: [email protected].

I've already sent it to the email associated with your Geotech account ([email protected]).
However, I have also now sent it to your gmail account.

[profesor]

I've already sent it to the email associated with your Geotech account ([email protected]).
However, I have also now sent it to your gmail account.

thank you.
I tried a circuit like this many years ago.
portable cassette tape kit.
I connected tx coil to receiver coil speaker output to input.
I adjusted the feedback with volume. It was working fine on big metals.