Lrl from Italy

[mustefa ubram]

Hi Mustafa
I think you need to change Q1 with bc183 in your proteus

hi
q1 is in orginal schematic pnp (bc170).I replaced 557 with 170

[v_gh]

I did not had Frequency in your circuit, but when change this part Oscilloscope Showed Frequency
Also bc170 is NPN No PNP

[FrancoItaly]

my latest lrl

Hi All

This is my latest lrl, it's very similar to the first but with a 8Mhz quartz oscillator, it's more easy to build because I give the pcb of this stage and the only fix is to try the right valour of C2,C3 and C4 to have from 2 to 4V output voltage. In my case I have used 1pF for all the capacitors (It depends on the parasitic capacitance of the PCB). The antenna may be a simple stylus and L1 is the same, 3 turs air core, 1cm x 1cm. The components are soldered directly on copper, does not need any hole. The sensitivity is slightly better but maybe depends on subsequent amplification that I made adjustable. In the display stage I use 3 leds but it's possible to use from 1 to ... what you want. The transistors are BC183c or others silicon NPN type with high beta, the diodes are 1n4148 or others. With a scope you must control that at Tr1 emitter there is about 8V signal, you may change C1 for better result.

Best Regards

[FrancoItaly]

Hi All

Touching the antenna input the output voltage decreases slightly and this confirms proper functioning.

Best Regards

[tanrila]

Hi All

Touching the antenna input the output voltage decreases slightly and this confirms proper functioning.

Best Regards

thanks master franco i build your new lrl i can detect mobil field and lamp field with
best regard

[moving]

Ciao Franco,sono nuovo in questo forum,credi che il tuo ultimo progetto postato e"piu"efficace nel rilievo oro sepolto rispetto al precedente ? sai credo , e ne sono convinto che il fenomeno esiste,grazie ma ,estremamente difficile da captare. vorrei assemblare questo progetto ed effettuare prove sul campo , un campo assolutamente predisposto per l"esame in questione.

[Nicolas]

thanks master franco i build your new lrl i can detect mobil field and lamp field with
best regard

You mean by this is Electrostatic???

I advice Franco to eliminate this frequency for lamp field and mobil field

Thank dear for your suggestions

[Qiaozhi]

Ciao Franco,sono nuovo in questo forum,credi che il tuo ultimo progetto postato e"piu"efficace nel rilievo oro sepolto rispetto al precedente ? sai credo , e ne sono convinto che il fenomeno esiste,grazie ma ,estremamente difficile da captare. vorrei assemblare questo progetto ed effettuare prove sul campo , un campo assolutamente predisposto per l"esame in questione.

Please read the forum rules -> Basic Rules of the Forums
and make your posts in English.

[moving]

Ok, administrator, I apologize for the inconvenience, i'll write" in English.

[FrancoItaly]

Hi moving

My latest lrl it's similar to the first (I mean like performance) but it's more easy to build, in fact, just find the right value for C2, C3 and C4 in order to have an output voltage of 1 to 6V. If you have a test field You can easily check the operation.

Best Regards

[FrancoItaly]

Hi Tanrila

Receiving signals from mobile phones or from other sources is a side effect, also common to metal detector, but it is a sign of proper functioning, no need to change the frequency that I think is the best.

Best Regards

[mustefa ubram]

hi franco
one question :
Why signal is in c8 AND c9 is impulsive?
why is not a squared signal?
This impulsive is emitted in the environment?

[FrancoItaly]

Hi mustefa ubram
The signal in C8 is impulsive because the TR1 stage is an active high pass filter. I don't know Where the impulse goes, the lrl is a passive receiver.
Best Regards

[mustefa ubram]

my new anttena
franco Which version of your lri is the best kind?

[FrancoItaly]

I think that stylus antenna and coil antenna are very similar. The stylus antenna may be elonged with greater sensibility.
Best Regards