Metal Snooper

[nudels]

I have one of these too, with a depth range of about 2 inches max in ideal laboratory conditions!

[Götz von Berlichingen]

What a weird Mix of Hi-Tech (PCB Coil) and extreme simple Circuit
(single Transistor and extra Radio as Receiver).

[Max]

What a weird Mix of Hi-Tech (PCB Coil) and extreme simple Circuit
(single Transistor and extra Radio as Receiver).

Hi,
yes... it's really old stuff... I made similar in my early years of MDs... MW radio stuff.

In this case radio can be either MW or LW kind.

The circuit is a simple oscillator... you tune the radio to ear a note...when metal is near the oscillator change frequency and signal is not received at the radio... very simple.

So, it's a kind of off-resonance md.

Kind regards,
Max