Lrl from Italy

[Pahom]

Originally Posted by rxlock2

I don't want a file in lay format, but in PDF format like in the photo so I can print it
mail: rxlock2@gmail.com
Τhanks.

Laot is a simple program, very easy to master. And you can also print the layout on a printer. All tutorial videos are on YouTube. Nothing complicated. And look at your mail.

[rxlock2]

Originally Posted by Pahom

Laot is a simple program, very easy to master. And you can also print the layout on a printer. All tutorial videos are on YouTube. Nothing complicated. And look at your mail.

Thank you very much

[omar]

Originally Posted by rxlock2

can someone put the PCB in PDF for printing

https://top4top.io/downloadf-2551qpyt80-rar.html

[rxlock2]

Originally Posted by omar

https://top4top.io/downloadf-2551qpyt80-rar.html

Thank you

[abdou2014]

are there layout pcb ?

[Pahom]

Originally Posted by abdou2014

are there layout pcb ?

Oh how, you missed a lot, everything is in the posts above ... and the boards and the circuit have not changed.

[abdou2014]

THERE IS ONLY PDF FILE

[omar]

I think that Franco's device needs a second independent device that transmits radio frequencies AM / SW modulated regular sound waves from 500 Hz to 2.5 kHz. to stimulate the phenomenon.

[omar]

When a sample is placed in a constant magnetic field and stimulated (perturbed) by a time-varying (e.g., pulsed or alternating) magnetic field, NMR active nuclei resonate at characteristic frequencies. Examples of such NMR active nuclei are the isotopes carbon-13 and hydrogen-1 (which in NMR is conventionally known as proton NMR). The resonant frequency of each isotope is directly proportional to the strength of the applied magnetic field, and the magnetogyric or gyromagnetic ratio of that isotope. The signal strength is proportional both to the stimulating magnetic field and the number of nuclei of that isotope in the sample. Thus in the 21 tesla magnetic field that may be found in high resolution laboratory NMR spectrometers, protons resonate at 900 MHz. However, in the Earth's magnetic field the same nuclei resonate at audio frequencies of around (2 kHz) and generate very weak signals

https://k.top4top.io/m_2556md8ot0.bmp

[FrancoItaly]

Originally Posted by omar

I think that Franco's device needs a second independent device that transmits radio frequencies AM / SW modulated regular sound waves from 500 Hz to 2.5 kHz. to stimulate the phenomenon.

It is possible, but the L/C resonant circuit is in the FM range and therefore the frequency of the external oscillator must be tuned to this frequency (or one of its harmonics).

[omar]

My idea, my friend Franco, is as shown in the pictures below. An MP3 player can be used in the car as a transmitter by adjusting the capacity, although its energy is low, but it is ready and cheap. And good luck.

[FrancoItaly]

Originally Posted by omar

My idea, my friend Franco, is as shown in the pictures below. An MP3 player can be used in the car as a transmitter by adjusting the capacity, although its energy is low, but it is ready and cheap. And good luck.

I sincerely think that a dedicated, more versatile system would be better, also because it should be used together with the lrl, i.e. permanently connected to it.

[Pahom]

[QUOTE=FrancoItaly;161971]It is possible, but the L/C resonant circuit is in the FM range and therefore the frequency of the external oscillator must be tuned to this frequency (or one of its harmonics).
Omar on this board has one small mistake c16 33n must be based on Tr5

[rxlock2]

[QUOTE=Pahom;161980]

Originally Posted by FrancoItaly

It is possible, but the L/C resonant circuit is in the FM range and therefore the frequency of the external oscillator must be tuned to this frequency (or one of its harmonics).
Omar on this board has one small mistake c16 33n must be based on Tr5

Pahom is right.
As Omar has installed C16, the circuit does not work.

[omar]

thank you my friends. the mistake has been fixed. And good luck

https://top4top.io/downloadf-2557vef7b0-rar.html

[Inna]

Thanks Omar, due to my personally needs of container size and how I engineered my device, I had to rearrange and redesign the pcb's tracks. I had checked them one by one, but I hadn't noticed the error on c16. So that's the only mistake made, is everything else ok?

[omar]

Originally Posted by Inna

Thanks Omar, due to my personally needs of container size and how I engineered my device, I had to rearrange and redesign the pcb's tracks. I had checked them one by one, but I hadn't noticed the error on c16. So that's the only mistake made, is everything else ok?

My apologies to you, my friend, and to the others. Unfortunately, I did not check the drawing because the circuit is simple, but now I checked the drawing. There are no errors, it is only the location of the 33nF capacitor, and it has been corrected. And good luck

[Pahom]

[QUOTE=omar;161992]My apologies to you, my friend, and to the others. Unfortunately, I did not check the drawing because the circuit is simple, but now I checked the drawing. There are no errors, it is only the location of the 33nF capacitor, and it has been corrected. And good luck[/QUOTOmar, everything is fine. For this, forums are created. To communicate, share, help whenever possible. The board is working, only as Franco recommended, it should be done on two-sided fiberglass. Then there is less fluctuation at the control point.

[omar]

The pieces must be soldered immediately after cleaning the board, because the copper oxidizes quickly and the problem arises. And it must be ensured that the pieces are welded correctly, because weak welding means a weak connection or separation, and this fails the device to work. Transistors whose gain is not less than 450hfe should be used, such as BC183C, bc184c, or bc173c. For example, (BC547C is not suitable, as it will not achieve the required gains, and therefore the device has little sensitivity.) To increase the gain and extend the FM range you can use 2N7052 OR 2N7053. The device suffers from the need for frequent rebalancing like other conventional metal detectors.( What is not known is whether the full FM signal reaches the detection diode)

[Pahom]

Originally Posted by omar

The pieces must be soldered immediately after cleaning the board, because the copper oxidizes quickly and the problem arises. And it must be ensured that the pieces are welded correctly, because weak welding means a weak connection or separation, and this fails the device to work. Transistors whose gain is not less than 450hfe should be used, such as BC183C, bc184c, or bc173c. For example, (BC547C is not suitable, as it will not achieve the required gains, and therefore the device has little sensitivity.) To increase the gain and extend the FM range you can use 2N7052 OR 2N7053. The device suffers from the need for frequent rebalancing like other conventional metal detectors.( What is not known is whether the full FM signal reaches the detection diode)

Thanks Omar! Cool transistors need to buy these !!!!

[FrancoItaly]

Some considerations:

if the sensor stage auto oscillates it means that the amplification is sufficient, provided that the oscillation does not occur due to an unsuitable pcb.

If transistors with sufficient gain are not found, R10 and R12 can be decreased, for example 470 ohms.

The voltage drop of the diodes does not matter since the voltage changes are measured.

The FM signal is processed in mixer stage TR2 and is not amplified further.

[Ertron30]

Originally Posted by omar

thank you my friends. the mistake has been fixed. And good luck

https://top4top.io/downloadf-2557vef7b0-rar.html

This file cannot be downloaded. do you have the lay6 file

[Inna]

Originally Posted by omar

My apologies to you, my friend, and to the others. Unfortunately, I did not check the drawing because the circuit is simple, but now I checked the drawing. There are no errors, it is only the location of the 33nF capacitor, and it has been corrected. And good luck

No problem Omar, indeed I personally thank you for posting your pcb, it served me a lot as a starting point for developing my circuit. The important thing is to collaborate, notice mistakes and correct them. We are human... I wanted to ask the more experienced ones, is the BC548C ok?

[omar]

The bc547c / bc548c / bc549c transistors have a gain in the lower limits of 420hfe.
The circuit needs to adjust and reduce the value of the resistance R12 to achieve the required gain with it. As our friend Franco said.

Note it has a wider bandwidth than the bc183c

[omar]

[]This file cannot be downloaded. do you have the lay6 file.

The download link is working.