Surf pi detector-MOD

[Qiaozhi]

So, is the SMW an IB detector or a VLF detector?

It's a VLF detector with an induction balanced coil.
The two acronyms refer to two different things.

[scs-bg]

I have made many detectors. This is the scheme of the best for searching. It has a well-working discrimination. But it is not impulse. It works with inductive balance VLF. Frequency 8-10 kHz. I apologize for the poor quality of the scheme. I am already old and I have no desire to draw it again. The scheme is working. Whoever made it will no longer want another detector. This is my gift to everyone.

[scs-bg]

Here's how it works

[boilcoil]

This is my gift to everyone.

Thank you.
I have heard about this scheme, and from the words of old seekers - it is realy very good detector.

Thanks again.

[scs-bg]

https://youtu.be/1f9hKo_mBFU?is=G7UDS4F3KUlBMO6_

[algan]

https://youtu.be/1f9hKo_mBFU?is=G7UDS4F3KUlBMO6_

Thank you very much, Sasho. Do you have a picture of the board? I would like to take it.

[scs-bg]

The board was designed with a discrete stabilizer. It was replaced with a L4940V10. There were other changes to achieve a good result.

[scs-bg]

There are copies of TL 061 in which a trigger effect occurs with a strong signal. It is good to change the input connection as shown in the picture. The circuit works very well with operational amplifiers tls 272 instead of CA 3240.

[GeoMax]

https://youtu.be/1f9hKo_mBFU?is=G7UDS4F3KUlBMO6_

Good job!!! The detector works better than most new modern detectors.

[scs-bg]

The picture shows the first experimental model. It doesn't look good, but it has been working great for many years.

[scs-bg]

Maybe the Chinese will like this detector too, and they are starting production very quickly...

[algan]

Hi Sasho, can you draw in red the connections of these hicks, first one hick after the transmitter and then the tl062 hicks that go to the ground balance and to the discrimination, and there is also a G and D switch there, what is it for? Yes, there is also a ground potentiometer there, the switches I assume are 4066, and for the inductance of the TX and RX coils or the number of windings, can you also write on the receiving coil, what are the values of the elements at the beginning of 5532?

[scs-bg]

I checked what i did years ago and corrected the diagram.It*s not pretty but it works. WARNING- this is not suitable for begginers and i don*t want to become a teacher.

[scs-bg]

Old version board with discrete stabilizer.

[algan]

Thank you very much Sasho, I would also like to ask about the resonance of the RX, is there a difference in the frequency up or down? If so, what is the difference? Or is it full resonance or is it equal to transmission?