hello franco what is the gold and silver phenomenon values ​​under the ground? Is it possible for you to provide information on this subject?

Unfortunately I don't have these data, official science doesn't recognize the phenomenon, I can only tell you that personally (like other forum members) I believe in its existence, having built and used tools that prove it. It is a complex phenomenon that acts on a wide range of frequencies and therefore it is possible to build instruments that rely on different frequencies. For now I have not been able to establish whether the phenomenon is the same for each type of metal and therefore there is a possibility of discrimination. Iron is certainly not detected and this is a nice plus.

Actually I have a specially made device .33khz sine wave is applied to the ground with two cables laid on the ground. There is a tda2030 audio output circuit. only amp values are changed. The receiver part is divided into 3 with a 3-step switch and fine-tuned with a potentiometer. Between 16khz and 19khz between 19khz and 22khz between 22khz and 26khz. There is no connection between the receiver and the transmitter. The antenna in the receiver is about 40 cm long. a coil is wound on a core as an antenna.

I think it is a system derived from geophysics.

I have improved the performance of my lrl, I cannot say exactly how much, as I no longer have the original test field available, however in my current land there is a point where the original lrl signaled a weak signal right nearby, instead with the modification there is a fairly strong signal at about 2 m. The modification essentially consists of increasing the frequency of the quartz to 20 Mhz and of tuning L1 / C10 on a harmonic frequency of the quartz. In addition, I made R10 as trimmer to vary more easily the gain of the sensor stage. I have also improved the display stage by putting a fine adjustment and a coarse to make tuning easier. In this way it is possible to "lock" the output voltage of the sensor stage for a wide voltage excursion. The oscillator circuit has been modified to obtain a waveform as distorted as possible, furthermore the frequency of the quartz has been increased to 20Mhz. In this way, harmonics are also generated, one of which (I suppose the 4th or 5th) is tuned with the resonant circuit L1 / C10. For this reason C10 is now a variable capacitor. I also attach the diagram of the power stage. However, any circuit that provides stabilized 12 V is fine. In my diagram I have put a red led that flashes when the voltage drops below 15.5 V. I also enclose a new "help". It is almost essential to have an oscilloscope available, in fact the values of the oscillator components vary greatly depending on the type of quartz,there are types of quartz harder than others to make oscillation. The calibration of the sensor stage serves to obtain the maximum gain without having oscillations.

I modified the help, in fact I realized that if the oscillator signal is too wide, it is difficult to set up as the signal reaches the base of TR2 also due to parasitic coupling.

crystal oscillator
 

good day

Mr.franco Italy
thank you for sharing project and helping others

don't know if someone asked or no but why you don't use ready oscillator
instead of crystal?
because running high frequency xt is a little bit hard at least at no projects i had success
so, i always use ready oscillators except projects that XT runs by microcontrollers.
i think many members that built your L.R.L also couldn't run XT but they don't know

thank you

https://s16.picofile.com/file/8428541100/xt_active.jpg

You are right, you could also use the "ready oscillators", but I find that the quartz version is the simplest, even most oscillates even without the capacitor between the emitter and the base of the transistor, in the range 2 - 10 Mhz in my opinion is the best choice. The same scheme also works with 20 Mhz, but it is more critical, also because we are at the frequency limit for quartzes that work in fundamental (harmonic). Furthermore it is necessary to have a waveform as distorted as possible, to have many harmonics and a signal of small amplitude in order not to radiate towards the sensor stage.

Hi FrancoItaly
I made your LRL with SMD components, but I don't know how much to tune the potentiometer screws to adjust it? (I'm looking for gold)
But sometimes when I tune the potentiometers, and walk to the refrigerator door, the LED lights up and the speaker beeps, and when I walk away from the refrigerator, the lights go out and the speaker does not beep!
Also, when I walk to the place where the toilet well has been dug, the lights and speakers turn on!
Does this device detect a magnetic field or ions?
Best Regards

I don't know (and I don't know if there is) a frequency just for gold. It is normal for there to be many sources of disturbance in the home. Very little is known about the phenomenon, indeed according to "normal" science it does not exist. In my opinion, since it works with an antenna, it is an electromagnetic field.

I would like to warn those who intend to make the 20Mhz version of my lrl to wait because, while the first one works perfectly, the other two, which I did later, have problems with signal instability. I am making substantial changes and think I have solved the problem. I will post the changes as soon as possible.

Good luck mister franco
waiting for your new lrl

Good afternoon Franco! Reading about a new project at 20 MHz, you constantly repeat that the waveform at the output of the generator should be DISTORTED as much as possible. Is this so or is it a translation error?

It is not an error, a distorted signal means that it contains harmonics of higher frequency, in our case: fundamental = 20Mhz, second harmonic = 40Mhz, third = 60Mhz, fourth = 80Mhz, fifth = 100 Mhz, always with decreasing amplitude. The L1 / C10 resonant circuit is tuned to one of these harmonics (I think 80 Mhz or 100 Mhz) and this makes the sensor stage more sensitive.

Thanks! Another question, in the circuit display 1, the capacitor c1 is indicated 10mf is it an electrolyte? The previous version specified 0.22mF.

C1 is 10 nF, in the previus version was 22 nF, however it is not very important, however too high values, 100 nF and more, can slow down the response, especially if you search with fast scans.

Thanks Franco! It remains to find out to what frequency to tune the input circuit L1 and C1, if I understood you correctly, then it should be approximately in the region of 80-100 MHz

In the L1 / C10 resonant circuit, by varying the capacitance of the capacitor, we see the amplitude of the signal, at the output of the sensor stage, increase when a harmonic of 20Mhz is reached, and then decrease moving away from it.

You say c10 is the one on the TP3 collector

As I understand it ..... you talked about a circuit with a quartz at 8 MHz, there in the circuit yes L1-C10. I asked you about the 20 MHz quartz circuit and there in the L1-C1 circuit. Thank you Franco, now I understand your explanation about harmonics.

The 20 Mhz lrl is a improvement of 8 Mhz lrl, C10 in the 8 Mhz sensor stage has been replaced with a variable capacitor.

Thank you dear friend :)

https://ibb.co/p0XJ5pP
hello i designed franco 80mhz i will try .:)

hello i designed franco 80mhz i will try .:)

Good evening Franco! Did you solve the problem with signal instability?