Lrl from Italy

[FrancoItaly]

I think this is no good, the better it's the stylus antenna.

[RIMES]

Thanks Mr Franco

[brs]

hi franco
Is the transistor bf240 increases the sensitivity of the machine, and you have a real testing ground

[FrancoItaly]

I can not test the Bf240, I'm not in Italy, Geo has had this idea, and we expect the result.

[Geo]

I can not test the Bf240, I'm not in Italy, Geo has had this idea, and we expect the result.

Hi Franco.
No better results with highter frequency transistor.
There is better sensitivity but the compass phenomenon is highter so we need to reduce the sensitivity. Total gain = 0 :lol:

Regards:)

[ouiarabe]

Hi all
it's bizard but if I connect the stylus antenna at the base of TR2 the mounting becomes more sensitive

[FrancoItaly]

Hi All,
It may be a good idea, but we must check whether does not appear the compass effect.

Best Regards

[ouiarabe]

Hi All,
It may be a good idea, but we must check whether does not appear the compass effect.

Best Regards
hi franco
I did some tests and there is no effect of the compass

[abdou2014]

it has been a long time I tried these methods . this device receives with the capacitor :D

[FrancoItaly]

Hi ouiarabe,
Have you noticed improvements with buried metals?

[ouiarabe]

Hi ouiarabe,
Have you noticed improvements with buried metals?

hi Franco
I have not a good test fields, I buried for nine months two small gold rings from a few grams.
I tested in a field where there has a Roman ruin, the device responds in two positions but I have not checked well because of the presence of many people and the prohibition for treasures research in my country .

Finally, please forgive me for my language

[brs]

the base of TR2
Not the best hand reveals the phenomenon

Increasing the lighting led when touching the antenna by hand

[brs]

hi franco
I want an alternative to Transstor bf240 to doing my experience for TR1

[FrancoItaly]

The transistor TR1 must have a very high gain and even a high operating frequency, then I think go well all the NPN transistors of the BC ...series (the "C" type has a gain greater than 500) and a frequency of more than 200MHz, BC239C and BC549C they are fine. The transistor BF... series they have a higher frequency of operation but a lower gain, thus they are not suitable.

Regards

[brs]

Thank you very much Franco

[ouiarabe]

hi Franco
and of course all other
after some tests I found that the antenna stylus connected to the base of TR2 makes it sensitive mounting static electrical charge as the neon lights of the high voltage pouteaux and of course the hit in the hand, the assembly becomes like a Zahori
I will attach a video
the antenna left is the original and which is in the right that is connected to the base of TR2

[ouiarabe]

Hi all
here is the video


https://www.youtube.com/watch?v=F1utYoRBidI

https://youtu.be/F1utYoRBidI

[FrancoItaly]

The test with the hand only indicates that the amplification is sufficient and that the installation is correct, but does not provide evidence that the LRL is working, for example, if L1 is composed of 5 turns the test with the hand is positive but does not work as LRL. The phenomenon is difficult to capture and probably will change depending on your location.

[brs]

why
5 turns not good

[abdou2014]

You had different results for the two antenna. what is their location, I think : L1 base of TR2 and L2 emitter of TR1 ?

[ouiarabe]

The test with the hand only indicates that the amplification is sufficient and that the installation is correct, but does not provide evidence that the LRL is working, for example, if L1 is composed of 5 turns the test with the hand is positive but does not work as LRL. The phenomenon is difficult to capture and probably will change depending on your location.

maybe you did not understand me
I mean by this video as left antenna detects the negative charges and the right detects the positive charges

[abdou2014]

You had different results for the two antenna. what is their location, I think : L1 base of TR2 and L2 emitter of TR1 ?

[FrancoItaly]

I did not do any experiment with other coil (L2) and the stylus antenna is directly connected to L1, also I do not think it's positive and negative ions, as the impedance of the input LRL is very low, what affects touching the antenna is the capacitance of the human body.

[brs]

hi franco
The impact of the compass and the sky that appear when there is a lot of padding
I want to explain to me more afraid that I have a lot of padding and whether the piece affects the operation of the device

[FrancoItaly]

I don't know what you mean for "padding".

[brs]

Amplification
sorry for my bad used a translator

[FrancoItaly]

You must decrease the amplification until the compass and the sky effect disappears.

[brs]

Amplification of capacitor or resistance

[FrancoItaly]

If you have the 3 leds version turn P1 for less sensibility, if you have 1 led version turn P2, I think that it's not necessary hardware change.

Best Regards

[brs]

thank you franco

[brs]

http://store1.up-00.com/2016-05/1462916372161.jpg

[FrancoItaly]

I don't understand, the scheme is correct, the presence of a target is signaled by an increase in voltage to the signal input (from sensor), then at out of IC3A the signal decreases (the signal is applied to inverting input). When signal at not inverting input of IC3B is more low then 6V (Determined by the R12 / R13 voltage divider) the out of IC3B goes low (zero volt) and then the LED lights up and the buzzer sounds.

Best Regards

[brs]

Thank you Franco
accept greetings

[abdou2014]

I want to make this change. is there anyone who is interested ?

[FrancoItaly]

Before making any changes you have tested the LRL on the field ? In my opinion my LRL works only in the 100Mhz range. The low pass filter is no critic as the output is a DC voltage
with some residual RF (8Mhz).

Best regards

[Mohlrl]

hi Franco. In your opinion, transistor with hfe 450 is good?

[FrancoItaly]

Yes I think it's ok, look " http://alltransistors.com/transistor.php?transistor=22466 ", 450 is the minimun value for " hFE " ( transistor gain ). Anyway for more gain you can increase C13 and/or C14. Any transistor BC...C series with 150Mhz frequency or more is ok.

[abdou2014]

location of the filter corrected .what is the resonance of LC circuit ? and why we not add a resistor for get a wideband .

[FrancoItaly]

LC resonance is about 100 Mhz, I have not measured accurately, It must be taken into account the capacitor formed by the BE junction of TR2 (about 10pF). C15 is a simple coupling capacitor with a very low impedance at the frequency of 8MHz, should at most is a simple high pass filter. The set of C15, D1, D2 and C16 constitute a full-wave rectifier, while TR5 operates in emitter follower with high input impedance and low output impedance. R15, R16, C17 and C18 constitute a lowpass filter to eliminate the residual signal at 8 MHz.
I repeat that the sensor stage is very critic for the high gain, in my opinion it should be built on a separate PCB, preferably double-sided, with components soldered directly on the copper of a part, while the other part is connected to ground and serves as a screen to prevent auto-oscillations. I will post again my original PCB.

[abdou2014]

So your device is Capacitive detector , and if we add an antenna in base of TR2 we have a Static and Capacitive Detector . I'm right ?

[goldfinder]

Sounds like he is using the capacitor as a scalar sensor to detect the gravity eminations of the minerals ( gold).
Goldfinder

[FrancoItaly]

I do not know if it is a Capacitive detector. Static presupposes very high impedance receiver, but it's not the case.

[abdou2014]

PLEASE Mr FRANCO WERE WE PUT THE VARIABLE CAPACITOR FOR TUNING. IN C9 OR C10 (8 MHz Stage). AND WHAT IS ITS VALUE?

[FrancoItaly]

In place of C 10 and the value is 22pF. Usually the variable capacitor has the range from 4 to 22pF. To test lower frequencies you must add in parallel a 10pF capacitor.

[abdou2014]

THANK YOU :)

[LRLMAN]

Hello dear friends I have a small obstacle to put to work my LRL I only need to complete the stage of Power-Display, I develop a PCB but this I did not work because the potentiometer 20k I put the device began to heat up and smelled burned and decided to review all the PCB but nothing; Now draw another PCB through the program called: Live Wire and PCBWizar and the program suits me the tracks as follows but I have the impression that even is not complete the PCB and I think that some lines should go to negative part and I would like to know if someone in the forum here can help me to complete the Power-Display Stage and can test it on field.

Regards.

LRLMAN.

[FrancoItaly]

Try to feed the part relating to IC2 (the stage display) with a stabilized power supply, obviously with 12V, excluding all the part related to 78l12 and IC1. With led off the absorption will be a few mA, if it is not so you have to check that there is no short circuit between the + 12V and ground. Leaving the power section disconnected connects the stabilized power supply instead of batteries and if the absorption is very high you have to control C1 and C3, sometimes it happens that the electrolytic capacitors are defective, otherwise it can also be a short circuit here between + 12V and ground.

[LRLMAN]

Try to feed the part relating to IC2 (the stage display) with a stabilized power supply, obviously with 12V, excluding all the part related to 78l12 and IC1. With led off the absorption will be a few mA, if it is not so you have to check that there is no short circuit between the + 12V and ground. Leaving the power section disconnected connects the stabilized power supply instead of batteries and if the absorption is very high you have to control C1 and C3, sometimes it happens that the electrolytic capacitors are defective, otherwise it can also be a short circuit here between + 12V and ground.



Ok thanks Dear Franco, but then... how do I know which are the tracks that are missing for the pbc is properly ?? and can work well? could you help me a little ?? please.

Thank you so much for your help Franco.

receive a big hug.

Lrlman.

[abdou2014]

Is it necessary MR Franco to make two power supply. One for sensor and one for display stage. And separate them. Because I have supplied both with a single supply ?

[abdou2014]

Here is my PCB 8 Mhz

[FrancoItaly]

No, there is only one power, 12V, that goes to sensor stage and to display stage. The only way to test PCB is to follow every track and make sure it complies with the wiring diagram.

[Hadi]

Hi Franco,
I have an idea. Can we use A/D uc and LCD display instead of display stage. That can to detect low signal from sensor stage.

[FrancoItaly]

It's a good idea, I built two lrls with 10 LEDs, for one I used a LM3914 and for the other I used a PIC16F88 but I think that the LM3914 it's the best choice. With 1 LED version you must connect the IC3A output to LM3914 input and change the inputs, that's output of sensor stage to non inverting input of IC3A and the cursor of P2 to R10. However, even the version with 3 LEDs works well, although less accurate.

[Hadi]

Thank you so much Franco.
I will try to reach best result and I'll send you hex file.
By the way how much the max voltage is in output of sensor stage? (I mean when 3 LED's are on)

[FrancoItaly]

The max voltage (theoretical) at output sensor stage it's about 8V. If without target signal the output is (for example) 4V we may suppose with a very large signal an output of 5V, that's 1V range, this range is amplified by the first operazional. If we suppose a gain of 6 the range at operational output it's (for example) 2 - 8V or 0 -6V.

[Hadi]

Thanks for your kindly guide.

[abdou2014]

is it more easy to get the center of target with your lrl than the vlf receiver lrl ?

[FrancoItaly]

I don't know the vlf/lrl, but in general the lrls are not able to make a pinpoint of the target as the VLF metal detectors, but the signal increases approaching the target and disappears completely right above the target.

[abdou2014]

is there a trick to determining target location. at what distance from target the signal disappears ? and is it necessary to be facing south direction ?

[abdou2014]

Franco LRL with True RMS :)

[FrancoItaly]

As I said signal disappears completely right above the target. Direction Nord/South or East/West it's not important for pinpoint.

[mustefa ubram]

hi to all.
hi franco .how are you?i miss you:)
I'm back after a long delay.I want to start rebuilding project Franco.I forgot a lot of information about the project.
dear franco :i have many question.please reply :)
When placed non-ferrous metals in the soil for a long time .What events or changes occur for electromagnetic state of the soil?

[FrancoItaly]

Hi mustefa ubram,
I'm fine, but I'm always in Switzerland close to my wife who is ill and therefore can not make any proof with my LRL. I do not have a valid theory on the phenomenon, but I think the important thing is that the phenomenon exists and can be revealed, the next step would be to distinguish gold from other metals. I appeal to all those who want to make changes to my LRL and I say that as the first thing must be able to operate the LRL on the ground with metal buried for at least a few weeks and only after they can think about changes.

Best Regards

[abdou2014]

Mr franco is that the frequency varies between countries, and what is the source of this signal, VLF transmitter station or natural magnetic field of earth ?

[mustefa ubram]

Hi mustefa ubram,
I'm fine, but I'm always in Switzerland close to my wife who is ill and therefore can not make any proof with my LRL. I do not have a valid theory on the phenomenon, but I think the important thing is that the phenomenon exists and can be revealed, the next step would be to distinguish gold from other metals. I appeal to all those who want to make changes to my LRL and I say that as the first thing must be able to operate the LRL on the ground with metal buried for at least a few weeks and only after they can think about changes.

Best Regards

I wish health for your wife

[mustefa ubram]

NEW PCB OF CRYSTAL LRL

[FrancoItaly]

watch these videos:

https://www.youtube.com/watch?v=lp35Ly8Cw1Q

https://www.youtube.com/watch?v=BUzyKuUQExE

https://www.youtube.com/watch?v=BQfyqmgCdcY

I ask Panos Pappas few details on the type of metal and even distance is revealed. To Mustefa I said: good work.

[mustefa ubram]

watch these videos:

https://www.youtube.com/watch?v=lp35Ly8Cw1Q

https://www.youtube.com/watch?v=BUzyKuUQExE

https://www.youtube.com/watch?v=BQfyqmgCdcY

I ask Panos Pappas few details on the type of metal and even distance is revealed. To Mustefa I said: good work.

Thank you franco
please send me panos pappas email in prvate message

[abdou2014]

Good work mustefa , do you have eagle or proteus file to share with us :)

[mustefa ubram]

Good work mustefa , do you have eagle or proteus file to share with us :)
sorry dear freind
i have altume format .

[abdou2014]

I never work with it , would you like to share just for have an idea , thanks

[pigeon]

HI ALL FRIEND

how I can use two antenna Franco lrl 3 leds?

thank you for all

[pigeon]

HI ALL FRIEND

how I can use two antenna Franco lrl 3 leds?

thank you for all

emplacement to fixed two antenna

[FrancoItaly]

2 or 3 antennas are connected togheter and we have more sensibility, but even if we stretch the antenna, for example, from 30 to 50cm or 60cm, we have a sensitivity increase. However often also the compass effect increases.

[pigeon]

2 or 3 antennas are connected togheter and we have more sensibility, but even if we stretch the antenna, for example, from 30 to 50cm or 60cm, we have a sensitivity increase. However often also the compass effect increases.


THANK YOU:)

[mustefa ubram]

franco
Does putting batteries in this way creates pores in the boxes in the works?

In general, the power supply does not need a separate box or differences?

[abdou2014]

Can I put bc548c or BC549c for ( Tr2 - Tr3 - Tr4 - Tr5 ) in place of bc 183c ?

[mustefa ubram]

Can I put bc548c or BC549c for ( Tr2 - Tr3 - Tr4 - Tr5 ) in place of bc 183c ?
no abdou2014
bc548 &bc549 is low gain transistor but bc183c is hi gain transistor

[dream_man]

Hi dear Mustefa ;
I've seen your Cristal 8 MHz PCB and faced to some questions. What are the components which I mentioned by the red lines in the below picture?.. one of them is L7812 regulator, but I dont know the capacitance of the rest of components.
Thanks for your contribution my friend.


http://i66.tinypic.com/wstn5u.jpg

[mustefa ubram]

Hi dear Mustefa ;
I've seen your Cristal 8 MHz PCB and faced to some questions. What are the components which I mentioned by the red lines in the below picture?.. one of them is L7812 regulator, but I dont know the capacitance of the rest of components.
Thanks for your contribution my friend.


http://i66.tinypic.com/wstn5u.jpg
hi freind
I hope you have understood correctly mean.I have specified the amount of three capacitors
best wish

[dream_man]

Thank you dear Mustefa for you fast and supportive reply. How about your results?.. have you achieved any good outcome using this 8MHz cristal circuit? ...

[dream_man]

Dear Mustefa, I think you forgot to draw the place of 3 turns filter on the board. Please locate the place of the filter if it is possible.

[pigeon]

hi freind
I hope you have understood correctly mean.I have specified the amount of three capacitors
best wish

hi all friend
how I can fix the antenna and the choke coil

can i use bc237 in place bc183


thank you

[mustefa ubram]

Dear Mustefa, I think you forgot to draw the place of 3 turns filter on the board. Please locate the place of the filter if it is possible.
Dear friend . There is LC circuit board.I have identified.Be careful:)
I never could I tested the device in action.Because I had no real purpose.

[mustefa ubram]

hi all friend
how I can fix the antenna and the choke coil

can i use bc237 in place bc183


thank you
You can not do not use the choke.Because you need to tune the resonance frequency.


Maybe you're using the bc237. Should be tested in reality.But need to hi gain.Choose high-gain transistor.bc183c Is good.

best wish

[dream_man]

Thank you Mustefa, But real purpose is rare and as Franco said we must test it by at least 2 months buried metals. ;)

[dream_man]

hi all friend
how I can fix the antenna and the choke coil

can i use bc237 in place bc183


thank you

Here I reply you by what Franco recommended earlier ;

"The heart of all the LRL is the high gain part consists of TR2, TR3 and TR4; if the gain is too large this part goes into oscillation and it's very unstable, if instead the gain is too low, the phenomenon is not revealed.I use the type BC183C transistors because I own a lot, but you can use equivalent types (BC109C, BC209C, BC239C and so on) the important thing is that they are NPN silicon with high "beta" (suffix "C"). The RF gain of the amplifier,for a certain range of frequencies, depends on the value of C13 and C14, the lowest value = less amplification and vice versa."

"The best antenna is a stylus 80cm-100cm. With 30cm it has the minimum sensitivity, the greater the length the greater the sensitivity. With these changes, it is possible to detect targets that were previously ignored, such as, for example, short time metals buried (1 month or more) in your test field."

Hope it helps you.

[mustefa ubram]

Thank you Mustefa, But real purpose is rare and as Franco said we must test it by at least 2 months buried metals. ;)
Right Franco

[pigeon]

Dear friend . There is LC circuit board.I have identified.Be careful:)
I never could I tested the device in action.Because I had no real purpose.

hi mustafa

is what you can give me a picture to facilitate
fixing the choke coil and the antenna

thank you very much

[abdou2014]

Mr Franco You Said That "for a certain range of frequencies, depends on the value of C13 and C14, the lowest value = less amplification and vice versa."
what is the maximum value of C13 C14 (for more gain) in remaining in Range of frequency wish ?

[pigeon]

Here I reply you by what Franco recommended earlier ;

"The heart of all the LRL is the high gain part consists of TR2, TR3 and TR4; if the gain is too large this part goes into oscillation and it's very unstable, if instead the gain is too low, the phenomenon is not revealed.I use the type BC183C transistors because I own a lot, but you can use equivalent types (BC109C, BC209C, BC239C and so on) the important thing is that they are NPN silicon with high "beta" (suffix "C"). The RF gain of the amplifier,for a certain range of frequencies, depends on the value of C13 and C14, the lowest value = less amplification and vice versa."

"The best antenna is a stylus 80cm-100cm. With 30cm it has the minimum sensitivity, the greater the length the greater the sensitivity. With these changes, it is possible to detect targets that were previously ignored, such as, for example, short time metals buried (1 month or more) in your test field."

Hope it helps you.


:) thank you

[mustefa ubram]

hi mustafa

is what you can give me a picture to facilitate
fixing the choke coil and the antenna

thank you very much
dear freind You can not have a fixed chokes.Because you need to adjust the resonant frequency and the air-core coil.You can test for proposed Franco 3turn coil and The parallel capacitor 22p.This is a fixed amount.
best wish

[pigeon]

dear freind You can not have a fixed chokes.Because you need to adjust the resonant frequency and the air-core coil.You can test for proposed Franco 3turn coil and The parallel capacitor 22p.This is a fixed amount.
best wish

ok thank you:)

[dream_man]

Hello dear Mustefa;
Your 8MHz crystal circuit has some problems. c8 is not located and R5 is not connected before c8 and c7. May you find more errors on that. I've drawn a circle on the wrong place in the below picture.

[brs]

hi frands
I'm placing
tr1 2n5551
tr2,tr3,tr4 and tr 5 C9014
but high sensitivity to influence the compass and the sky

[dream_man]

Hi there ;
Anyone has a correct and an updated PCB of 8MHz crystal circuit? ... Kindly upload it if you have.

[Hadi]

Dear Franco I have not experience in the construction of electronic musical instruments, electronic organs and other electoinic instruments but i have experience in physic's experiments.

If you make some experiments with nano-pulses in HV domain you will see that envelope of nano-pulses have almost perfect sawtooth wave shape - so it have infinite superpositions of both odd and even harmonics over wide frequenc range. If you succedd to make an Unipolar nano-impulse you will get pure potential impulse with zero current running. This kind of impulses are basic of scalar longitudinal waves. So am pretty sure that gold treasure radiate above described zero current - high potential impulses (remember burnt front-end LRL electronics of Alonso Geo and many others LRL hunters). And yes they (nano-impulse) influent E-field of your telescopic antenna and parallel tank-circuit changing amplitude and phase of your LRL. And they deca with 1/r law.

Best Regards from Russia
Enjokin4


Hello dear Enjokin4

I design this program and circuit. In this program, pulse train so you can change frequency and duty cycle and can to change delay of next pulses (OOK modulation).
The pulses are bipolar. Also you can change turns of second wire transformer to make bipolar high voltage.

[pigeon]

hi all friends

i have this projet by persian forum. it is correct:)

thank you

[pigeon]

hi

[pigeon]

:)if these projects are okay, help me make one

by persian forum

thank you all

[Napsterce]

Hello friends, in the 8mhz quartz version can i replace TR1-TR5 BC183C with BC550C? Is it better with stylus or with coil antenna? What kind of wire should i use for L1, what diameter and lenght? And last but not least, any experience with Franco,s lrl?

[FrancoItaly]

As I said every transistor BC...C series works well, then also BC550C works well. L1 it's not critical, you may use 1mm wire, 10 mm diameter and 10 mm in length. Stylus antenna is better, also more easy to build. I invite all those who have built my LRL to tell their experience in the field. This is also why I wanted to disclose my instrument. This is meant to be an open source project, in which everyone can work together to improve it.

[mustefa ubram]

The latest version of 8MHz LRL system with Polygon pcb.:)

I am busy completing projects

[Napsterce]

Mustefa which project is this, what schematic? Is that a voltage regulator or?

[dream_man]

The latest version of 8MHz LRL system with Polygon pcb.:)

I am busy completing projects

Great Job man. Please upload the latest PCB and let us make it to recover new results.

[mustefa ubram]

Mustefa which project is this, what schematic? Is that a voltage regulator or?
this is 8mhz franco circuit:)
My voltage supply is 16V.The circuit needs to 12V.I've used 12-volt regulator

[pigeon]

:frown:may be that it is the same mustafa

[pigeon]

:

[pigeon]

Mustefa which project is this, what schematic? Is that a voltage regulator or?

:) thank you MUSTAFA

[mustefa ubram]

:frown:may be that it is the same mustafa
my freind my name is mustefa not mustafa.
ok Maybe are like

[pigeon]

my freind my name is mustefa not mustafa.
ok Maybe are like


hi mustefa


I am not specialized in electronics but I try to do something:)

thank you

[Napsterce]

Hello, what are p1 and p2 used for in the 8mhz version? What do they tune?

[dream_man]

Hello, they adjust threshold and sensitivity of IC.

[vlf]

Hello Franco,
I built your 8mhz and display stage with 3 led. I am a radio amateur and my other hobby is the metal detector. I m impressed from your device. The main point is the connection (or mixing) between oscillator antenna and amplifier input. I had to set 2 wires instead 3 capacitors 1pf for out < 6V, may be the parasitic capacity is to high on my PCB . Perhaps I should separate the oscillator?
I think an extern stable 12 voltage regulator for battery is necessary?

Best Regards to all in this forum!

[FrancoItaly]

Hi vlf
I've used this trick in a copy of my LRL (I built 10 LRL). It's a system used by radio amateurs, I recommend using a separate PCB for sensor stage also for also to avoid auto-oscillations, but if you have < 6V and the voltage decreases when you touch the antenna the sensor stage it's ok. It's necessary a 12V voltage regulator, I repost here my original PCB for sensor stage and schematics, the power stage it's only in 1 led version, but it's necessary also in 3 leds version.Of course you can also use other solutions, I have also provided a low battery indication.

Best Regards

[mustefa ubram]

hi to all and franco
I finished the 8mhz project.Using the transistor bc 237c.The project is very high sensitivity .Ultimately device sensitivity is very stable
Reveals mobile radiation from a distance of 5 m.Reacts to the radio remote control of 1 meter.By touching the antenna output voltage is decreased.Everything happened according to Franco.(Sensitivity and reduced voltage by touching the antenna).
But today tested in practice:
About a year ago I buried my 2 gold coins.At a depth of about 60 to 70 cm.After a year I went there today for testing.Unfortunately, the device did not show any reaction:frown:I tested from different directions SE to North and East to West, North to South and vice versa.I use the new system of two modes: fixed and variable capacitors .I used the fixed type of capacitor 22p in parallel with the coil .In this mode I tested did not react devices:frown:I used the variable mode of the variable capacitor in parallel with coil And tested in various modes and again no result
Franco What do you think?
What is the problem? The purpose or the system?
please guide me?

[UltraLRL]

Maybe its not working at all!!:nerd:
Does any one have a field test???

[mustefa ubram]

Maybe its not working at all!!:nerd:
Does any one have a field test???
yes About a year ago I buried my 2 gold coins.At a depth of about 60 to 70 cm.After a year I went there today for testing

[FrancoItaly]

Hi mustefa,
Your LRL seems built properly, unfortunately I could not test my LRL in real research, I can only say that in my test field, as I said, I buried 5 silver coins, 25cm deph. Perhaps 60 or 70cm it is too deep to issue the phenomenon after a year, try buried at 20 cm. Try also to extend the antenna. Vanco Dojranliev says "40 cm depth ..2 gold rings 4 grams of 18k gold ..40 days buried "

https://www.youtube.com/watch?v=yR3tzT2Jd-g.


Best Regards

[mustefa ubram]

Hi mustefa,
Your LRL seems built properly, unfortunately I could not test my LRL in real research, I can only say that in my test field, as I said, I buried 5 silver coins, 25cm deph. Perhaps 60 or 70cm it is too deep to issue the phenomenon after a year, try buried at 20 cm. Try also to extend the antenna. Vanco Dojranliev says "40 cm depth ..2 gold rings 4 grams of 18k gold ..40 days buried "

https://www.youtube.com/watch?v=yR3tzT2Jd-g.


Best Regards
thank you franco
Do you think deep failing system?
10 silver coins placed on how deep it is appropriate to test?
And for how long?

[dream_man]

Hello Dear Franco ;
First of all thanks for publishing your LRL and answering our questions from simple to critical.
I'v not seen the rout of the selected items in your schematic, so I connected them as the below picture shows. I proposed the rout, please check whether is correct or not. In case of mistake, please recommend me how to do. thank you.

[pigeon]

hi all

please anyone have the pcb for this version

thank you

[dream_man]

Hello Dear Franco ;
First of all thanks for publishing your LRL and answering our questions from simple to critical.
I'v not seen the rout of the selected items in your schematic, so I connected them as the below picture shows. I proposed the rout, please check whether is correct or not. In case of mistake, please recommend me how to do.

1. In display stage, pin 1 of P2 is connected to R2 and the middle pin is connected to out of IC1A, but how about Pin 3 of P3?

2. Are connected R3,R4,R5, and R6 together? or they are connected to the inverting input (-) of IC2A, IC2B, and IC1B ?

3. I've downloaded your CompPcb.pdf of sensor stage, please upload the display stage as well if possible.

[FrancoItaly]

1. Pin 3 of P2 is not connected, P2 is used as variable resistance.

2. the inverting input (-) of IC2A, IC2B, IC1B and the output of IC1A are connected together.
R3/R4 to pin + IC2B --- R4/R5 to pin + IC2A -- R5/R6 to pin + IC1B.

3. I have PCB only of the sensor stage, the only that's critical. I think there is no problem for other PCBs.

Best Regards

[dream_man]

1. Pin 3 of P2 is not connected, P2 is used as variable resistance.

2. the inverting input (-) of IC2A, IC2B, IC1B and the output of IC1A are connected together.
R3/R4 to pin + IC2B --- R4/R5 to pin + IC2A -- R5/R6 to pin + IC1B.

3. I have PCB only of the sensor stage, the only that's critical. I think there is no problem for other PCBs.

Best Regards

Thanks dear Franco for your supportive and productive information.

[dream_man]

1. Pin 3 of P2 is not connected, P2 is used as variable resistance.

Best Regards

sorry Franco, how about the middle pin of P2? is it connected to the out of IC1A ?

[brs]

hi Mr. Franco
to increase the gain in the 8mhz device only increase the value of C13 and C14

[brs]

The device works I have a test field reveals a 3-meter 2 silver ring and some copper small cutting depth of 40 cm and I want beyond that disclosure Is there a way to increase earnings

[FrancoItaly]

Hi dream man,

Yes, the middle pin of P2 is connected to the out of IC1A.

Best Regards

[dream_man]

Hi dream man,

Yes, the middle pin of P2 is connected to the out of IC1A.

Best Regards

Thank you dear Franco, I'm drawing a new schematic of your LRL and will upload it in the upcoming hours ;)

[FrancoItaly]

Hi bsr,
Yes you may increase the value of C13 and C14 or you may decrease the value of R10 and R12 but the output of sensor stage must be lower than 6V. For increase the sensibility you must increase the gain of the first operational of display stage, the important thing is that it does not appear the compass/sky effect. Another thing you can try is to vary L1 / C10, for L1 test 2 turns and for C10 test 10-22-33pF and see if it changes the sensitivity for silver and copper.

Best Regards

[dream_man]

Hello Mr. Franco;
May you check this PDF schematic file of your LRL whether is correct or not, and please share your recommendations?
Thank you.

[FrancoItaly]

it seems right, but I suggest adding the "low battery" circuit which is the version with 1 LED.

[dream_man]

it seems right, but I suggest adding the "low battery" circuit which is the version with 1 LED.
Thank you dear Franco. I actually got the battery circuit from your 1LED circuit.
18Volt battery is connected to C20=100 Micro 25volt,--->100N---->L7812 Voltage reg--->C22=100 Micro 25v--->100N---> to circuit.
may you help more?.. whats the difference? ... I already drawn the 3 led version... "low battery" circuit, what does it do?

[mustefa ubram]

thank you franco
Do you think deep failing system?
10 silver coins placed on how deep it is appropriate to test?
And for how long?
Franco?????

[FrancoItaly]

in my experience 5 silver coins buried about 25cm for at least a month, but I think it is also important the type of soil.

[Napsterce]

Hello friends, i have built the sensor stage and on the output it gives a voltage under 1 volt and when i touch the antenna it decreases for about 0.10volts. And it is not stable, at connecting to the 12v source it gives 0.36v and when i touch the antenna it goes to 0.26v, after a 2-3 minutes it goes to 0.56v and when i touch the antenna it goes to 0.40v. Is that ok or not? Thank you all.

[pigeon]

hi all

someone had the pcb:)

thank you

[Napsterce]

After resoldering the L1 the starting voltage on the output is 1.36v and it keeps increasing, after 5 minutes it went up to 2.86v. When i touch the antenna it decreases the output for 0.10-0.15v. Is this ok or is there some problem? Franco? I checked all the soldering joints.

[dream_man]

Hello dear Franco. Sorry, how much is the VCC of IC in "low battery indication"?,,, 12V or 18V?

[FrancoItaly]

VCC of IC in "low battery indication" it's 12V. I suggest you adjust P1 so that "low battery" is on when the battery voltage drops below 16V.

[dream_man]

VCC of IC in "low battery indication" it's 12V. I suggest you adjust P1 so that "low battery" is on when the battery voltage drops below 16V.
thank you dear Franco

[Napsterce]

Dear Franco, i have built the lrl, but the leds glow all the time and when i touch the antenna one of them turns off. When I adjust the gain and threshold to more sensitive and less gain only the red led glows and when i touch the antenna it turns off. Is this correct or it should be the other way, when i touch the antenna the led to start to glow? Everything is built by your schematics, the display stage is with 3 led diodes with lm358p.

[brs]

dear franco
Thank you to everyone help you perfect man Franco

[dream_man]

Thank you dear Franco for supporting us.
Here I attach both "8MHz - Quartz LRL Power + Display (3 Led)" and "8MHz - Quartz LRL Sensor Stage + Power Stage with Low Battery Indicator + Display Stage (3 LEDs)".
Hope it helps other friends to make their PCBs.

[pigeon]

Thank you dear Franco for supporting us.
Here I attach both "8MHz - Quartz LRL Power + Display (3 Led)" and "8MHz - Quartz LRL Sensor Stage + Power Stage with Low Battery Indicator + Display Stage (3 LEDs)".
Hope it helps other friends to make their PCBs.

MR DREAM MAN

have you the pcb please.

thank you

[dream_man]

MR DREAM MAN

have you the pcb please.

thank you

Hello friend;
I've not made any pcb yet. sorry for that.

[pigeon]

Hello friend;
I've not made any pcb yet. sorry for that.

ok thank you:)

[Napsterce]

Dear Franco, i have built the lrl, but the leds glow all the time and when i touch the antenna one of them turns off. When I adjust the gain and threshold to more sensitive and less gain only the red led glows and when i touch the antenna it turns off. Is this correct or it should be the other way, when i touch the antenna the led to start to glow? Everything is built by your schematics, the display stage is with 3 led diodes with lm358p.

Franco?

[FrancoItaly]

" only the red led glows and when i touch the antenna it turns off " this is correct.

Best Regards

[Napsterce]

Thank you Franco, you're the best.

[dream_man]

Here I attached a new PCB of the 8MHz - Quartz LRL Sensor Stage + Power Stage with Low Battery Indicator + Display Stage (3 LEDs), and its schematic. Hope it helps you my friends.

[pigeon]

Here I attached a new PCB of the 8MHz - Quartz LRL Sensor Stage + Power Stage with Low Battery Indicator + Display Stage (3 LEDs), and its schematic. Hope it helps you my friends.


:);) thank you very much my dear friend:p

[FrancoItaly]

Hi dream man,
very good work, in this way my LRL looks really professional, although I use simulation programs, for PCBs and for schemes still use hand.

Regards

[pigeon]

Hi dream man,
very good work, in this way my LRL looks really professional, although I use simulation programs, for PCBs and for schemes still use hand.

Regards

;)

[dream_man]

Hi dream man,
very good work, in this way my LRL looks really professional, although I use simulation programs, for PCBs and for schemes still use hand.

Regards

Thank you dear Franco. Actually I tried to copy the sensor stage exactly from your "PcbCpmp.PDF" file. :)

[Golden]

This LRL detects the target in front ..or sideways? How high is more sensitive?
Thank you .

[dream_man]

Hello dear Franco;
1. May I know what will happen if I decrease the amount of C17 and C18 from 100nF to 33nF?
2. Can we use Darlington NPN transistors like BC517 or MPSA13 ?
Thank you.

[FrancoItaly]

Hi dream man,
1. C17 and C18 are not critical, with R15 and R16 constituite a low pass filter to eliminate the residual signal to 8MHz. This filter may be necessary if the sensor stage is far from the rest of the circuit (a few tens of cm, as in my case).

2. In my opinion darlingtone transistors have too much gain and there would be the risk of self oscillations.

Best Regards

[dream_man]

Thank you dear Franco :)

[Hadi]

Hello Franco,

I replaced 100nF with 33nF and I tested it with cellphone and ion that was sensitive of before. Also I used BC517 instead of 183 or other I hadn't any problem in my circuit.
On collector of TR4 I have 2.5 volts and on out that's about 0.26 V.
The reason of I can to detect mv is ADC of uC. I used ATmega328.

In your circuit when we have more train pulses in antenna will be more voltage in out.
We get pulses not frequency so when the frequency of antenna goes to high the pick up signals goes to faster and better.

Dear Franco do you accept to change local oscillator with high frequency crystal such as 28MHz.

B.R

[FrancoItaly]

Hi Hadi,
If when you touch the antenna the DC signal (0.26V) decreases I think that's ok, but remember that if at TR2 base we have for example 1 mV (at 8 Mhz) and the DC output is 5.2V for a given sensor stage and in your sensor stage you have also 1 mv at input and 0.26 at output, this means that your sensor stage has a 20 times lower gain (0.26 X 20 = 5.2).
I use sometimes Arduino that has the same micro-controllor and the ADC is 10 bit, that's 5 mV resolution, this means that a variation of less than 5mV is not perceived.
My lrl works in the range 3-10Mhz without changing any value but I don't know with other higher frequencies, definitely not work with lower frequencies. I think that there is an optimal ratio between frequencies of antenna and internal oscillator.

Best Regards

[UltraLRL]

I use sometimes Arduino that has the same micro-controllor and the ADC is 10 bit, that's 5 mV resolution, this means that a variation of less than 5mV is not perceived.

Best Regards

it's for 5v as reference voltage and 10 bit ADC (2 ^10 = 1024)

ADC resolution = Vref / 1024

for Vref=5v resolution is about 5 mv
for Vref=2.56v resolution is about 2.5 mv


for higher resolution,lower Ref Voltage is Recommended

[FrancoItaly]

You are right, but do not know if it's worth to use a micro controller, I think 3 LEDs are sufficient.

[Golden]

Hello Franco,
How detect this LRL the target : front or.. sideways ?
Thank you.

[mustefa ubram]

Franco, for a maximum voltage of 5 V output must be changed?
Is it possible to reduce the output voltage with op-amps

[Napsterce]

Hello Franco, the lrl is complete. Plastic box, antenna used from another device, wooden handle and the battery is external with 12.47 volts power from it. I have tested it and it reacts with the north, i dont get other signals, only that. What should i do to stabilize the compass effect? Thank you.

[FrancoItaly]

for Golden: the lrl detects front and sideways.

for mustefa: if you use a device that works at 5V you must reduce the output voltage of sensor stage (that may be also 8V or greater with a big target). Yes you may use an operational or a 5V zener diode and set the output voltage of sensor stage at about 4V.

For Napsterce: all the lrl works with a 12V stabilzed power. The only way to reduce the compass effect is to reduce the gain.

Best Regards

[mustefa ubram]

f
for mustefa: if you use a device that works at 5V you must reduce the output voltage of sensor stage (that may be also 8V or greater with a big target). Yes you may use an operational or a 5V zener diode and set the output voltage of sensor stage at about 4V.


Best Regards
thank you franco
How much output voltage sensor stage for standby?(When there is no target)

Which is part output is better? for connection to the Microcontroller?out put sensor stage?

[Napsterce]

Dear Franco, i have test field with cooper, will it give results, is it working with cooper or only gold?

[FrancoItaly]

Hi mustefa,
6V for me is the better value for standby, the output of sensor stage is the only output for other devices, Microcontroller or operationals.

Best Regards

[FrancoItaly]

Hi Napsterce,
I have no experience with all metals, but surely Lrl detects gold, silver and brass for my direct experience. More time the metal is buried, more strong is the phenomenon.

Best regards

[Napsterce]

Wikipedia: Brass is a metal alloy made of copper and zinc; the proportions of zinc and copper can be varied to create a range of brasses with varying properties;

Franco, according to this it is going to detect copper, we will know after a month or two. Thank you.

[dream_man]

Hello dear Franco ;
There are several capacitors like 100nF and one 33nF and so on. Which type of capacitors are better on your LRL? I mean ceramic disk, multi layer, polyester, or MKT ?
thanks for responding.

[FrancoItaly]

Because we are in the radio frequency bandwidth (8MHz) the better choice are the ceramic disk.

[dream_man]

Thanks dear Franco.

[Napsterce]

The lrl is tested at 3 places, 1 place without results, the other 2 places got all 3 led's glowing at gain set to 40-50% and sensibility set to 40-50%. The results are not 100% sure because it's not on a test field.

Franco i have two questions for you, how to tune the lrl to be sure it's not catching false signals and should i make a pcb with different values for L1 and C10 like in the picture? Thank you.

[pigeon]

The lrl is tested at 3 places, 1 place without results, the other 2 places got all 3 led's glowing at gain set to 40-50% and sensibility set to 40-50%. The results are not 100% sure because it's not on a test field.

Franco i have two questions for you, how to tune the lrl to be sure it's not catching false signals and should i make a pcb with different values for L1 and C10 like in the picture? Thank you.

hi:)
I do not see any picture

[Napsterce]

Sorry, some problem with uploading, here it is. ;)

[pigeon]

Sorry, some problem with uploading, here it is. ;)


thank you

[FrancoItaly]

Hi Napsterce,

I did it this way: instead of C10 I used a 22pF variable capacitor and then I soldered in parallel the 22pF capacitor and so I covered a range from a few pF to 44pF. It is to keep in mind that there is always the base/emitter capacitance of TR2 (about 10pF) in parallel to C10. Same procedure for L1, first I sold L1 with 4 turns and I vary the capacity of C10, then I sold L1 with 3 turns and so on. I use a soldering iron 12V powered.
What can disturb LRL are radio frequency transmitters located nearby and there is no way to eliminate them. Regarding the compass effect should decrease the sensitivity. It is possible that by varying L1 / C10 can be achieved a reduction of this effect without decreasing the sensitivity.

Best regards

[FrancoItaly]

You may use also a varactor diode instead of C10.

[Napsterce]

Thankyou Franco, i will test on a test field soon.

[dream_man]

Hello dear Franco;
what range of the output voltage is more comfortable for this circuit? .. 1 volt? or 2..3..4..5?
I've configured two 1pF capacitors in series and have 1 volt output.. Is it ok? .. or I need to remove one of them to increase the output voltage?

[FrancoItaly]

Hi dream man,

In the sensor stage the purpose is to obtain the maximum amplification but without there being self oscillation. If you used BC...C transistors I think that the gain is enough, then is necessary to act on the amplitude of 8MHz signal which goes to the base of TR2. The total value of C2, C3 and C4 is added to the parasitic capacitance of the PCB, in a case I did not use capacitors but only the capacitance of two neighboring tracks of the PCB and in another case, two twisted wires. So you should remove C3 and C4 and for C2 you should find the right value for an output of about 5 - 6V.


Best regards

[dream_man]

Thank you dear Franco for replying. So you mean that 1volt is low for output of sensor and must be between 5 to 6 volt?

[Napsterce]

I made two lrl's by Franco's schematics and they have output 5 to 6 volts and when i touch the antenna it decreases. If I am correct if treasure is found the voltage will drop even lower and maybe to 0 volts, is that correct Franco?

[FrancoItaly]

Hi dream man,

Yes but perhaps the lrl could work well with only 1V. 5V ensure that we have the maximum possible gain.

Best regards

[FrancoItaly]

Hi Napsterce,

No the presence of the target is marked by an increase of the signal.

Best Regards

[dream_man]

Hi dream man,

Yes but perhaps the lrl could work well with only 1V. 5V ensure that we have the maximum possible gain.

Best regards

Thanks Franco. Cheers
:cheers:

[mustefa ubram]

hi franco
Is there a difference between the output voltage in the face of a large and small target ?

For example, the maximum output voltage of the sensor for a coin is 6 volts and for a 20cm*20cm is 8 volts?Or is else?

Which parameters in this circuit is always fixed for various targets?
the minimum distance between the target and sensor For a coin dating back 500 years Subsoil and a large target 1 year old Subsoil output voltage is equal?
Or against the large target is always higher voltage And old creates only more sensitive?

best wish

[FrancoItaly]

Hi mustefa,

Unfortunately I have little experience with the LRL in the real research so I can not answer any of your questions. I decided to publish my LRL because other members of the forum could help develop this project not only to improve but also to better understand the behavior on real field.

Best Regards

[FrancoItaly]

As several new members of this forum have asked me privately tips for building my LRL, want to do a little summary about its construction and calibration.
The quartz and TR1 constitute the internal oscillator, TR2 is the mixer to which the 8Mhz signal arrives along with the "phenomenon" picked up by the antenna. TR2, TR3 and TR4 are the high gain amplifier, TR5 takes the signal (rectified by diodes) with high impedance and on the emitter there is the signal with low impedance. R15, R16, C17 and C18 are a low pass filter that cancels signal residues at 8 Mhz. I repost schematic and PCB. It's better to use a double face PCB, on one side we sold the components and the other side there is the shield
connected to ground, to avoid self oscillations. It's preferable to use transistors type BC...C because the high beta (gain), I use BC183C because I have a lot but work well also BC549C, BC109C, BC239C and others. All sensor stage is powered by 12V stabilized. For the first test do not connect quartz then look at out point, the DC voltage must be 0V. If not the stage is self oscillating then you must decrease the gain by changing C13 and C14 (from 560pF to 470pF or less) until there are no more oscillations.
Now connect quartz and measure out voltage, if the voltage is yet 0 you have to control the emitter of TR1, if the oscillator is ok it must be a 8Mhz signal of few volts peak to peak, otherwise change C1, for example from 330pf to 470pF or more. Signal out is better in the range 5-6V, if it is more then 6V you have to decrease C2,C3 and C4, sometimes it's sufficient the parasitic capacitance of PCB (removing C2, C3 and C4) or you can use instead of C2-C3-C4 two wires of about 6 cm twisted between them. If signal out is less than 5V you have to increase c2-C3-C4, for example if you use only C2 you have 1pF, if you use only c3-C4 connected in series you have 0.5 pF and so. To test if everything is ok touch the antenna and the out must decrease (100 - 200 mV or more). The target is signaled by an increase of the output voltage.

[FrancoItaly]

oops I forgot schematic and pcb

[FrancoItaly]

I want to add that the sensor stage is very sensitive and must maintain his calibration away from electromagnetic sources of interference. The same measuring instruments affect the function. I recommend using the oscilloscope only to control the operation of the oscillator, but not use it to measure the amplitude of the signal on the collector of TR3 and TR4, as this will radically change the output signal. The only useful measure without "side effects" it's the DC voltage at output of sensor stage. A useful indicator of good functioning is that the DC output is stable, but if there is superimposed an oscillation of a few hertz or more this means that there is a self-oscillation. I want to mention in passing that this LRL, in the first version, was a RF sniffer that self oscillated, but the output was stable and, quite by accident, I realized that functioned as LRL.

[Napsterce]

Hello Franco, this is my pcb layout by your pcb hand drawing, it's not double sided, how should i shield it? The small pcb is display stage, will it make some problems to be like this or should i remove it from there? If you notice some irregularities please tell me. I am using 12v battery but it is not regulated and the voltage is 12.47 and keeps going down as i use the lrl (i don't use it more than 12v), should i put a regulator or is it ok like this? Thank you.

[FrancoItaly]

Hi Napsterce,

the shield is not strictly necessary, but you can use a foil of aluminum glued on the lower part of PCB or another PCB. I advise against the use of a 12V battery which feeds directly the sensor stage and the other circuits, You have to use 2 X 9V batteries (then 18V in total) and a 7812 (IC stabilizer), I repost here the schematic. The display stage close to sensor stage do not create problems, but for me it's important hold your hand quite far from sensor stage then I recommend using a long enough handle (25-30 cm).

Best Regards

[Napsterce]

Hi Franco, i have aluminium foil which is with glue (it's like duct tape but it is made from aluminium), i will glue it to the bottom side of the pcb and i will connect it to ground (battery negative). Also i am in process of building the second lrl and in the second one i will made the 2x9v battery power supply with 7812 IC and i will make a comparation which one is better. I'm giving the lrl's names N°1 and N°2. N°1 will be with 2x9v power supply, L1 = 3 turns and C10 = 22pF. N°2 will be with 12v battery, L1 = 2-4 turns and C10 = 22pF + 22pF variable capacitor. Why you advise against using 12v battery? The voltage is stable, it needs at least 1 hour using to reduce the voltage from 12.47v to 12.20v. Also on N°1 u use stylus antenna 60cm and plastic handle 20cm long. N°2 is in process of building but the handle will be also 20-25cm long and a stylus antenna (still searching for it). Also wanted to ask you, how about connecting 60cm antenna on C9-C10-L1 (your antenna connector) and 3 smaller antennas (10-15cm) to TR2? Or to connect them together with the big antenna? Best regards.

[FrancoItaly]

If the battery voltage is stable use it as well, but I prefer the stabilization. Regarding the antennas I would try the one at a time.

Best Regards

[afshin]

As several new members of this forum have asked me privately tips for building my LRL, want to do a little summary about its construction and calibration.
The quartz and TR1 constitute the internal oscillator, TR2 is the mixer to which the 8Mhz signal arrives along with the "phenomenon" picked up by the antenna. TR2, TR3 and TR4 are the high gain amplifier, TR5 takes the signal (rectified by diodes) with high impedance and on the emitter there is the signal with low impedance. R15, R16, C17 and C18 are a low pass filter that cancels signal residues at 8 Mhz. I repost schematic and PCB. It's better to use a double face PCB, on one side we sold the components and the other side there is the shield
connected to ground, to avoid self oscillations. It's preferable to use transistors type BC...C because the high beta (gain), I use BC183C because I have a lot but work well also BC549C, BC109C, BC239C and others. All sensor stage is powered by 12V stabilized. For the first test do not connect quartz then look at out point, the DC voltage must be 0V. If not the stage is self oscillating then you must decrease the gain by changing C13 and C14 (from 560pF to 470pF or less) until there are no more oscillations.
Now connect quartz and measure out voltage, if the voltage is yet 0 you have to control the emitter of TR1, if the oscillator is ok it must be a 8Mhz signal of few volts peak to peak, otherwise change C1, for example from 330pf to 470pF or more. Signal out is better in the range 5-6V, if it is more then 6V you have to decrease C2,C3 and C4, sometimes it's sufficient the parasitic capacitance of PCB (removing C2, C3 and C4) or you can use instead of C2-C3-C4 two wires of about 6 cm twisted between them. If signal out is less than 5V you have to increase c2-C3-C4, for example if you use only C2 you have 1pF, if you use only c3-C4 connected in series you have 0.5 pF and so. To test if everything is ok touch the antenna and the out must decrease (100 - 200 mV or more). The target is signaled by an increase of the output voltage.
Hi Dear Franco
thank you for guidance members, you described your lrl parts how do work except one,and that is L1,C10 filter role.If this lrl works in 8 Mhz but this LC frequency is high about 100Mhz,is it low pass filter or high pass or band pass or band stop filter? What is it role? And if we eliminate it what will happen?
Thank you

[Napsterce]

Dear Franco, can i use wooden box made from thick (3mm) wood or it is better to be in plastic box?

[FrancoItaly]

L1/C10 is pass band filter, if you remove L1/C10 or change values (more than 3 turns or less than 2 turns) the lrl don't work. The 8Mhz signal is somehow modulated by the "phenomenon" and this may vary from 3 to 10 Mhz. I can even add that frequencies of about 60 kHz do not work.
Much as regards the box, I always use plastic (easier for me to work) but I would think the wood is suitable, since there is not involved static electricity.

Best Regards

[brs]

dear franco
If we put instead of 8 mhz 9 or 10 mhz Are performance differs

[afshin]

L1/C10 is pass band filter, if you remove L1/C10 or change values (more than 3 turns or less than 2 turns) the lrl don't work. The 8Mhz signal is somehow modulated by the "phenomenon" and this may vary from 3 to 10 Mhz. I can even add that frequencies of about 60 kHz do not work.
Much as regards the box, I always use plastic (easier for me to work) but I would think the wood is suitable, since there is not involved static electricity.

Best Regards
Hi dear Franco,Thank you,
But It seems to be a band stop filter,Because the LC resonance waves received by the antenna go to the circuit ground with a minimum Impedance by LC, instead of
go to the base of Tr2 for mixing
and modulation with the 8 Mhz
,and it is strange. actually All frequencies pass and go to mixing and modulation except the LC frequency!!
while it should be inverse.
actually if this is a pass band filter has to be this form,I drew
What is your opinion dear franco?
Best regards

[mustefa ubram]

Hi dear Franco,Thank you,
But It seems to be a band stop filter,Because the LC resonance waves received by the antenna go to the circuit ground with a minimum Impedance by LC, instead of
go to the base of Tr2 for mixing
and modulation with the 8 Mhz
,and it is strange. actually All frequencies pass and go to mixing and modulation except the LC frequency!!
while it should be inverse.
actually if this is a pass band filter has to be this form,I drew
What is your opinion dear franco?
Best regards
hi freind
You are misunderstanding the concept of filter.When used electronics components that are full use.You painted the wrong input and output filter.In the picture You drew of capacitance and inductance are virtually out of the circuit Only have a connected base with circuit Not applicable in the circuit.

https://en.wikipedia.org/wiki/Low-pass_filter

[mustefa ubram]

hi franco
I have about 2.5 volts in standby mode the sensor output.And about 6 volts when the full reaction.
Is the low 2.5 volts?
In this case a very high sensitivity to the waves

[FrancoItaly]

Hi afshin,

L/C pass band filter at the resonance frequency it has a very high impedance and being placed between the antenna and ground leaves pass without attenuation only the resonant frequency signals, while it is almost a short circuit for the other frequencies.

Best Regards

[FrancoItaly]

Hi mustefa,

the output voltage is ok in 1-6V range, but I recommend about 5V because this way ensures that the sensor stage has the maximum gain possible without distortion, however also 1V can be compensated with a higher amplification in the display stage. The output voltage depends on two factors, one it's the sensor stage gain and the other is the amount of 8Mhz signal that goes to base of TR2. This is why I recommend to remove (or rather not sold immediately) quartz and find the right values for maximum gain without self-oscillation. Only after we can determine the values for C2 / C3 / C4.

Best Regards

[abdou2014]

Mr Franco you say that 3 turns running well in your region italy and switzerland ,What you recommended for the southern countries , to add a turn or remove a turn ? Thank you !

[FrancoItaly]

For my experience 2 or 3 turns work well, 1 or 4 turns do not work. For other country I don't know, but I think it's the same thing, you just have to try.

[brs]

dear franco
If we put instead of 8 mhz 9 or 10 mhz Are performance differs
Reply

[afshin]

Thank you dear franco and mustefa

[FrancoItaly]

Hi brs,

The gain of the sensor stage also depends on C13 / C14 and then increasing the frequency (from 8 to 10Mhz) also slightly increases the gain. However during calibration we determine the appropriate value for C13 / C14 for maximum amplification can be useful for that frequency. Changing the quartz (and therefore the frequency) after the calibration certainly increases a little the gain. The situation is different if you've noticed a different sensitivity to a given metal.

Best Regards

[brs]

Thank you dear franco

[pigeon]

Here I attached a new PCB of the 8MHz - Quartz LRL Sensor Stage + Power Stage with Low Battery Indicator + Display Stage (3 LEDs), and its schematic. Hope it helps you my friends.

hi dream man


can you give me the part +/- battery?.


I have to make a switch?

thank you very much:)

[pigeon]

hi dream man


can you give me the part +/- battery?.


I have to make a switch?

thank you very much:)

:(:angry: help me please

[Napsterce]

Here it is my friend.

[pigeon]

Here it is my friend.


thank you:)

[pigeon]

hi all friends


i have built dream man pcb I use a bc190c place bc183c is that they have the same location.

i have not electricity in the pcb no power:D

help me soory for the little english

thank you

[Napsterce]

Pigeon have you fixed the problem? What pcb have you made?

Franco tell me your opinion about MFD, do you think that your lrl in combination with MFD transmitter will give better results? If I'm not wrong your lrl catches the phenomenom and the MFD transmitter should amplify the phenomenom (actually it amplifies the metal's frequency which i think is very close to the phenomenom). Also i want to mention that by my last tests the lrl catches the frequencies emitted by radio/tv antenna and phone (gsm/hspa/lte) antenna but it doesn't catch frequencies emitted by police walkie talkie antennas (i don't know at which frequencies any of this antennas work).
Best regards.

[FrancoItaly]

I don't think that MFD may help with lrl because the frequencies are very different but I have not done any testing, maybe a harmonic of the MFD can happen in the range of LRL.

[Napsterce]

Dear Franco, MFD frequencies for gold as listed on forums an on MFD manuals are 5khz for gold and 8.7khz for silver. I think that in earlier posts you said that your lrl works around this frequencies. Thank you.

[FrancoItaly]

My lrl basically is a receiver tuned about 100 - 150 Mhz which detects anomalies in this range, then very far from 5 -7 Khz.

[FrancoItaly]

Several years ago I made tests with MCD and dowser and found that this system is too influenced by the human mind and therefore unreliable, at least in my case.

[Napsterce]

Yes that is coreect but i will try to use the MFD transmitter with your lrl. Like i said, i hope that it will amplify the phenomenom field so it would be easier to be catched by your lrl. The MFD you have built was with powered L rods? By what schematic you have built the MFD? Thank you.

[Qiaozhi]

Yes that is coreect but i will try to use the MFD transmitter with your lrl. Like i said, i hope that it will amplify the phenomenom field so it would be easier to be catched by your lrl. The MFD you have built was with powered L rods? By what schematic you have built the MFD? Thank you.
http://www.geotech1.com/cgi-bin/pages/common/index.pl?page=lrl&file=/projects/mfd1/index.dat

[FrancoItaly]

I don't remember well but the MFD was a NE555 oscillator and I touched the oscillator output,
my body was like an antenna. The frequencies were 32Hz for gold and 42Hz for silver, but, I repeat, the results were not satisfactory.

[dream_man]

hi all friends


i have built dream man pcb I use a bc190c place bc183c is that they have the same location.

i have not electricity in the pcb no power:D

help me soory for the little english

thank you
Hello pigeon;

[brs]

Hello my friends
Amplify the phenomenon of the field
MFD
Frequency that penetrates the ground
HZ , KHZ OR MHZ

[brs]

Do FM transmitter circuit, for example, it helps to amplify the phenomenon

[Napsterce]

Brs have you tried this or it's just an opinion? What should be the input of the fm circuit? Where to connect the output, in the ground like MFD or in air? Thank you.

[brs]

Just a question I'm not an expert in the transmitter circuit or phenomenon happens I hope that the experts the likes of Franco I support us with information

[FrancoItaly]

The phenomenon is very little known, even to many does not even exist. I do not think you can make changes without completely changing my LRL. My advice is to build my LRL and see that it works properly and only then can you think of some adjustment, mainly the L1 / C10 frequency. However, even so my LRL is quite sensitive, since I privately know that a forum member found some gold coins (dating back about 200 years ago) to 15 m away. Do not ask other details because I myself do not know them, but I have no reason to doubt. This discovery demonstrates that gold needs a long time to be revealed and therefore is not very suitable to perform tests.

[dream_man]

Hello dear Franco;
I did some tests by 2 months buried cooper and silver coins and unfortunately just one LED turns on near the test field. I tested your Varactor Idea along with L1 from 2 to 9 turns. In 2 turns, I have 5.5 volt which has low sensitivity to electrical waves like wireless phone (30 cm 3 LEDs will be on). On the other hand, when I increase the number of turns of L1, the output voltage drops and it goes to be more sensitive to the waves (3 meters 3 LEDs). I realized that lower output voltage brings more sensitivity.
There is another important point. If my test was right, it shows just 1 LED turned on. So I think we must increase the sensitivity in revealing section in display stage. Is it possible to do such idea by decreasing R1 and increasing R2 in display stage?
Thank you dear Franco. overall its my results.

[FrancoItaly]

Hi dream man,

Yes it's possible for have more gain to increase R2 and decrease R1, the important thing is to avoid compass effect. Also only one led on in field test it's acceptable, because there are many variables in play, metal type, soil type, time of burial. Test with wireless phone are not important, you have to test in a real field with buried target.

Best Regards

[dream_man]

R1 and R2 in display stage?

[FrancoItaly]

yes

[dream_man]

Thank you Franco. I'll test it and reply my results.

[pigeon]

Hello pigeon;
hi dream man
thank.but i have problem the lrl not work les not work?!

[mustefa ubram]

hi franco
I've tested the sensor output with 3 -2-1 capacitor of 1p.(c2-c3-c4)

The output voltage for each of the different

with 3 capacitor:2.5v

with 5 capacitor:5v

with 1 capacitor:6.2v
Which is the best situation?

[mustefa ubram]

hi franco
I've tested the sensor output with 3 -2-1 capacitor of 1p.(c2-c3-c4)

The output voltage for each of the different

with 3 capacitor:2.5v

with 2 capacitor:5v

with 1 capacitor:6.2v
Which is the best situation?
edited

[FrancoItaly]

In theory there is no difference because the gain does not change, but if you wanted to increase the gain you can use the 3 capacitors and then have 2.5V and increase C13 / C14 until you have about 5V, but it is better to increase the gain of display stage, especially to avoid self oscillations.

[dream_man]

Hello dear Franco;
As you mentioned earlier, after preparing the circuit, we must disconnect c2,c3 and c4 and measure the output voltage, it must be zero. Then you suggested using a 1pF cap instead of c2,c3 and c4 and measure the output voltage, if it is lower than 5 we must increase c13 and c14. What about high amplification and self oscillation If we increase c13 and c14 in order to obtain a greater amplification?,,, I mean, is there any bad side effect on this circuit if we increase c13 and c14 in order to have a 5 volt output?... which one is better, using 1 single 1pF or using three 1pF in series and increasing c13 and c14? .. sorry for this question

[FrancoItaly]

Hi dream man,

We have to have some gain in the sensor stage and this depends mainly on the amplification of TR2 / TR3 / TR4, unfortunately (unlike operational amplifiers) can not be established during the design phase, so we must act on C13 / C14 to get the correct gain. I recommend for this operation to disable the oscillator and to vary C13 / C14 for maximum gain (no self-oscillation).Once it has obtained the maximum gain you can find the right value for C2 / C3 / C4.

Best Regards

[dream_man]

Thank you Franco for replying;
but how to ensure that we have the maximum gain. after disconnecting c2,c3 and c4, what output voltage we must have in the TR5 emitter?
by increasing the C13 and 14 we increase the output voltage while quartz is disconnected. So the main question is finding the right value for c13 and 14. Please recommend a way to realize the right value.

[FrancoItaly]

Hi dream man,
while quartz is disconnected you must have in the TR5 output 0 volt. With quartz connected and c2,c3 and c4 disconnected you may have a few volts at output and this is a parasitic coupling and this is not negative (if the signal is stable and the sighal goes low by touching the antenna). On the contrary connect C2/C3/C4 for about 5 volt at output, however, it is not necessary to have at all costs 5 V, a lower gain at this stage may be offset by the display stage.

Best Regards

[dream_man]

Thank you dear Franco for your productive information;
I disconnected the quartz and increased C13 and C14 to 4.7nF (472 tag) and at this value I have 0.05 volt in the TR5 emitter. Then I connected the quartz and in place of C2 and C3 I replaced a 3pF and 27pF in series and got a total capacitance of 2.7pF. At this state, the TR5 emitter has a 4.85 volt. Is it correct that I configured those capacitors in series to get 2.7pF ? or this value is high?... whats your suggestion if any? ... thank you in advance dear Franco.

[FrancoItaly]

I think it's perfect, every installation is a special case, which depends on the tolerance of the components, especially the gain of the transistors and the parasitic capacitance of the PCB.
I also want to celebrate the thousandth post of this thread and I hope that many of you are able to build my LRL. I will add that with my LRL has been made a very, very important find.

[Napsterce]

Hello Franco, important find like a find in the circuit, or an important find like gold, silver... 😃😃

[dream_man]

Hello Franco...
Really fantastic... after the changes I've mentioned above, I tested the circuit at home. Surprisingly, I got one LED on near refrigerator and I thought that is because of its electricity wire but it was not. After that I've opened the refrigerator's door and after a while when the air came out all 3 LEDs turned on. I think the weather inside the refrigerator is ionized and circuit catchs it. It's great Franco. At least for me it responds.