Lrl from Italy

[Dubulumach]

Both FrancoItaly designs work but you will have big problems catching old rusty iron and otyher non noble metals because all of them create the phenomenon when were long time earthed.

FrancoItaly device need good Gold and Silver classifier to work as full valuable lrl. Think about how to make working classifier for gold. Without classifiewr device is like ordinary PI detector but on much higher distances.

D1,2= 1N60 (AA119)

Best regards
Dubulumach

[FrancoItaly]

Both FrancoItaly designs work but you will have big problems catching old rusty iron and otyher non noble metals because all of them create the phenomenon when were long time earthed.

FrancoItaly device need good Gold and Silver classifier to work as full valuable lrl. Think about how to make working classifier for gold. Without classifiewr device is like ordinary PI detector but on much higher distances.

D1,2= 1N60 (AA119)

Best regards
Dubulumach

I do not want to make controversy, but according to my experience and that of other people my lrl is sensitive to all non-ferrous metals, so also copper, bronze and other alloys (and of course gold and silver), but not iron. However it is possible that in certain terrains this can happen, for example Geo says that he has not succeeded in making it work. So surely the terrain is very important and I take note of your experience.

[VECTROUM]

Amplicier pcb

Hello

It is possible to post the pcb drawing of the antenna amplifier?

Thank you on advance.

[FrancoItaly]

Hello

It is possible to post the pcb drawing of the antenna amplifier?

Thank you on advance.

Sorry, I don't have, but it's very simple.

[VECTROUM]

Amplifier pcb

It is seperate pcb, correct?
Because i have allready contructed the sensor and display pcb's.
If someone have made it please send me the drawing at geortimas@gmail.com.

Thank you in advance.

[havoc88]

Antenna PCB + Parts Overlay

The antenna PCB and parts overlay.
PCB size 2cm X 2cm

[FrancoItaly]

The antenna PCB and parts overlay.
PCB size 2cm X 2cm

this is a good job, a valuable help for those who are not very practical with electronics and this is also the spirit with which I started this thread, in fact I decided to make available to all my lrl both in the spirit of open source and both because it could improve with the help of all the members. The original project was born by chance with the sensor stage that self-oscillating, but it was quite critical and dependent on the design of the pcb, later I added the quartz oscillator and the version with CD4046, in which we measure the phase variations and not the variations in amplitude. The last improvement is the antenna amplifier, made by a member of this forum, as I said before it is a circuit that amplifies the "phenomenon" and that makes the tuning of the sensor stage less critical, because in this way it is not necessary to obtain the maximum gain at the sensor stage, with the risk of self-oscillation.

[havoc88]

Mr. Franco we appreciate your goodwill to share your work and your knowledge with us.

[VECTROUM]

Thank you Havoc88 you are superb.
Thank you also Francoitaly for your excellent job on this lrl.
I have completed building it and i noticed that is very sensitive to the horizons.

[FrancoItaly]

Thank you Havoc88 you are superb.
Thank you also Francoitaly for your excellent job on this lrl.
I have completed building it and i noticed that is very sensitive to the horizons.

As I said in "helps.txt" you have to reduce gain until the compass effect disappears.

[FrancoItaly]

I modified the coupling between the antenna and the amplifier stage with a second coil wound on L1 (I call it L2), in this way there is a better adaptation between the impedances in play and ultimately a greater gain and a better selectivity. In this way there is a greater amplification for the "phenomenon" but not for the compass effect. At the moment I have no way of trying other changes that I leave to you as a task. In my prototype I did not put C10 (there is only the base / emitter capacitance). You can try to put a capacitor in parallel with L2 in order to tune it as L1 / C10, this may be in the 22pF-47pF range. L2 is wound over L1 and you can use a plastic holder on which to wrap first L1 (3 turns) and then L2 (2 turns).

[VECTROUM]

Franco lrl

Hello, i want to connect a meter in order to visualize sensor readings and i want to ask in wich output i have to connect it.

Thank you in advance.

[FrancoItaly]

Hello, i want to connect a meter in order to visualize sensor readings and i want to ask in wich output i have to connect it.

Thank you in advance.

You can connect a meter at output of sensor stage (TR5 emitter).

[VECTROUM]

Thank you for your awnser, may i ask wich pin of bc183c is the output?
e,c, or b?

Thank you in advance.

[FrancoItaly]

Thank you for your awnser, may i ask wich pin of bc183c is the output?
e,c, or b?

Thank you in advance.

e = emitter.