Lrl from Italy

[abdou2014]

the DC Gain in display stage , P2 and R2 .

[liudengyuand]

Has anyone succeeded?

[havoc88]

Excuse me friends. Is this CD4046 PCB "working" or not ? I've tried this part overlay with no luck.
Are the parts in the right order or not ? If it's working which is the pin or part that I can take an output for LM3917 VU meter ?

Thanks in advance !

[FrancoItaly]

I have not tried this PCB so I can not give any judgments. My advice is to make the sensor stage on a separate PCB and fine-tune it. Then you can add the other stages. I attach here the original PCB I used in all models and I suggest to make it double-faced, with the bottom face attached to the ground. This prevents oscillations.

Best Regards

[havoc88]

Thank you Franco for your time plus your work!!

[Milad.salsa]

hi franco very tnx for publish your project .
i have a queistion,can your circuit sense a metal in 2meter or more under ground???(depth)
because i sense metel in 60cm or less

[FrancoItaly]

The operating principle of lrls is that a metal (non-ferrous) buried for some time emits a kind of signal (which we call "phenomenon") that can be revealed to dozens of meters away and (I suppose) to several meters of depth . The greater the burial time the greater the distance and depth to which it can be revealed. I think a 200 or 300-year-old buried metal can be revealed by a lrl to a few meters in depth, but I think the depth also depends on other causes, such as terrain and maybe even atmospheric conditions. The phenomenon can also be revealed to about 2 meters above the ground.

[Milad.salsa]

thank you franco you are a great man.i test your circuit in a place that mw wave was very low and your circuit dont worked then i test it in a place with mw wave and your circuit worked very good.now this circuit work by radio wave?

[Hadi]

Originally Posted by FrancoItaly

The operating principle of lrls is that a metal (non-ferrous) buried for some time emits a kind of signal (which we call "phenomenon") that can be revealed to dozens of meters away and (I suppose) to several meters of depth . The greater the burial time the greater the distance and depth to which it can be revealed. I think a 200 or 300-year-old buried metal can be revealed by a lrl to a few meters in depth, but I think the depth also depends on other causes, such as terrain and maybe even atmospheric conditions. The phenomenon can also be revealed to about 2 meters above the ground.

Hi dear Franco
For long time buried your system can be revealed metal about 20 meters.
Thanks

[FrancoItaly]

Originally Posted by Milad.salsa

thank you franco you are a great man.i test your circuit in a place that mw wave was very low and your circuit dont worked then i test it in a place with mw wave and your circuit worked very good.now this circuit work by radio wave?

Hi Milad.salsa,

What do you mean by mw wave? Surely the input circuit is tuned around 100Mhz, fm range. It's interesting to know the frequency you've noticed.

Best Regards

[FrancoItaly]

Originally Posted by Hadi

Hi dear Franco
For long time buried your system can be revealed metal about 20 meters.
Thanks

Hi Hadi,

You mean you found a metal 20 meters away?

Best Regards

[Hadi]

Originally Posted by FrancoItaly

Hi Hadi,

You mean you found a metal 20 meters away?

Best Regards

The system is available to doing this performance.

B.R

[kaligula]

Originally Posted by payam20

here my pcb files
its 2bl side ( one side as franco said ground )
i put each component where to have the least effect to other one . becuase of its ground it have to much low noise .
what do you think dear franco . need any changes ??
sry for my english Untitled.jpg

This pcb has error at first sight, 7812 is shorted

[kaligula]

Originally Posted by pigeon

NICE JOB

Where I can found this display pcb layout

[kaligula]

Originally Posted by kaligula

This pcb has error at first sight, 7812 is shorted

Its OK, I found corected pcb

[ford]

Can I use p1=20k and p2=500k in 3led display stage ?
I haven't 22k&470k potentiometer.

[kaligula]

Originally Posted by ford

Can I use p1=20k and p2=500k in 3led display stage ?
I haven't 22k&470k potentiometer.

I think it's ok, it's not a big difference

[kaligula]

Does anyone have made it with this pcb?

[ford]

When I touch antenna, led turn on and voltage increase!
What is problem?
Output voltage is between 5 V and 6 V.

[FrancoItaly]

Sometimes it has also happened to me, the test simply serves to determine if, by touching the input, there is some change in output. This way we are sure that no stage is in saturation or inhibition. The only reliable test is with a metal that has been buried for some time.

Best Regards

[ford]

Thanks Franco

Can it detect buried metal pipes?

I tested it but I can't detect any thing!

I'm sure that there is very buried metal in our places

Best Regards

[kaligula]

One more question about the potenciometers. Which one can be with on/off switch and which one is better to be multiturn for better results?

[FrancoItaly]

Hi ford,

Lrls can reveal gold, silver, copper and their alloys as long as they have been buried for some time and are insensitive to iron and steel. You have to have a test field where you have to bury some objects like silverware or coins at a depth of about 20 cm and wait 3/4 weeks (or more depending on the type of terrain).


Best Regards

[FrancoItaly]

Hi Kaligula,

No need for special potentiometers as On / off switch or multiturn.

Best Regards

[kaligula]

Originally Posted by FrancoItaly

Hi Kaligula,

No need for special potentiometers as On / off switch or multiturn.

Best Regards

Ok, but to not put additional switch I want to put potentiometer with switch. I don't know to which one is better, to 470k or 22 k?