Lrl from Italy

[taher5739]

In my first lrl (self oscillating) the lower strips are not needed, in fact the lower screen is used to prevent self-oscillations. I advise against using this version, I made the version with oscillator just to make the lrl less critical to build. One way to trigger the self oscillation is to use a lower strip to connect the collector of TR2 with the base of TR1 or between the collector of TR3 with the base of TR2 via an appropriate (small value) capacitor. In this way two points out of phase of 360 degrees are connected. The only possible advantage of this version is that with it you are sure to have obtained the maximum amplification. As I said in the past this lrl derives from a bug detector that auto oscillated providing a stable signal capable of revealing the "phenomenon".

Thank you so much Mr. Franco
Do you mean this

https://imgur.com/a/Zx5zjsE

"use a lower strip to connect the collector of TR2 with the base of TR1 via an appropriate (small value) capacitor"

[FrancoItaly]

Thank you so much Mr. Franco
Do you mean this

https://imgur.com/a/Zx5zjsE

"use a lower strip to connect the collector of TR2 with the base of TR1 via an appropriate (small value) capacitor"

Yes.

[alisuri]

Yes.

Hi

I already built the original version of the LRL. The critical tests concerning voltages, touch ...
work well.
Is it necessary to impose the modifications like amplification.
Thanks
Ali

[FrancoItaly]

Hi

I already built the original version of the LRL. The critical tests concerning voltages, touch ...
work well.
Is it necessary to impose the modifications like amplification.
Thanks
Ali

In previous posts I suggested increasing R2 (from 220K to 560K) and decreasing R1 (from 150K to 56k) to increase the gain. Furthermore, to make P1 adjustment easier, 2 resistors (22K), one on the + 12V side and the other on the ground side should be placed in series with P1. The exact values of the 2 resistances must be found experimentally because it depends on the output value of the sensor stage (connected to the + input). If you increase the value of a resistance, you must also decrease the value of the other, so that their sum is in the range 30 - 50K. The ideal value is when P1 is set to maximum to the right, the first LED lights up and the buzzer sounds.

[alisuri]

In previous posts I suggested increasing R2 (from 220K to 560K) and decreasing R1 (from 150K to 56k) to increase the gain. Furthermore, to make P1 adjustment easier, 2 resistors (22K), one on the + 12V side and the other on the ground side should be placed in series with P1. The exact values of the 2 resistances must be found experimentally because it depends on the output value of the sensor stage (connected to the + input). If you increase the value of a resistance, you must also decrease the value of the other, so that their sum is in the range 30 - 50K. The ideal value is when P1 is set to maximum to the right, the first LED lights up and the buzzer sounds.

Thank you very much for the suggestions.
Ciao

[Arash]

pcb with antenna amplifier

Complete pcb with antenna amplifier
You can assemble one coil or two coils
I assembled, Sense is better

[FrancoItaly]

Good job, I advise you to mount the sensor stage first and calibrate it and then mount the rest.

[hoshi]

thank you very much sir franco

سلام
بدون خداحافظی نمیرفتین
بنده فقط ای دی شما رو اد کردم و به همین خاطر شماره من برای شما نمایش داده شده پس احتیاجی به نگران شدن شما نیست
ممنون از همکاریتون

[Qiaozhi]

سلام
بدون خداحافظی نمیرفتین
بنده فقط ای دی شما رو اد کردم و به همین خاطر شماره من برای شما نمایش داده شده پس احتیاجی به نگران شدن شما نیست
ممنون از همکاریتون

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

[hoshi]

Hello
Sorry I wanted to send a private message to this user.
After that I did everything I could not clear this text.

[havoc88]

I 've got a problem with the final version of 8MHz Franco's LRL build by Arash.
I've found a route (part) mistake in LM358 port, that's ok, working perfectly now but my main problem is that the TR5 (Q5 in current pcb) output is 3.15v no matter what i do, with crystal on or not.
I've double checked everything. Resistors, capacitors, nothing.

I upload the part that is wrong in pcb for anyone who made it



Any idea ?

[havoc88]

OK I found the fault, the silk screen in Arash PCB shows reversed every transistor image but marked correctly in pins -> EBC not CBE. I reversed them and now it's working as it should be.

[Arash]

pcb

The pcb tested, and making a lot, is fine and works well
Volume is okay, wires need to be properly connected, design is for the volume multi turn, you will replace the wire for the normal volume
It is better for you to read the content written by Mr. Franco

[havoc88]

Mr. Franco and friends.
Everything works perfectly when antenna is directly to base of TR2, it senses electrical signals, compass effect (maybe 99% ) but then, when I connect the antenna to the amplifier makes the detector not working at all (always outputs constant max signal and no effect no matter what) like it overdrives everything. Any clues?

[FrancoItaly]

Mr. Franco and friends.
Everything works perfectly when antenna is directly to base of TR2, it senses electrical signals, compass effect (maybe 99% ) but then, when I connect the antenna to the amplifier makes the detector not working at all (always outputs constant max signal and no effect no matter what) like it overdrives everything. Any clues?

The potentiometer must be adjusted for maximum sensitivity, which often does not coincide with maximum amplification. Too much amplification can cause self oscillation.