Lrl from Italy

[toorani]

hi dear franco
now with Touch antenna,out put tr5 10mvolt Increases,Is that right?

with decrease c2/c3/c4 From 1.8p to 1p ,out put voltage Decreases(3.8 volt),Is that right?

with decrease c1 From 560p to 370p,out put voltage Increases(5.2 volt),Is that right?

also antenna through L1 connected to ground,as a result,The shield and antena Are connected,Is that right?

Thank you so much.

[FrancoItaly]

Originally Posted by toorani

hi dear franco
now with Touch antenna,out put tr5 10mvolt Increases,Is that right?

with decrease c2/c3/c4 From 1.8p to 1p ,out put voltage Decreases(3.8 volt),Is that right?

with decrease c1 From 560p to 370p,out put voltage Increases(5.2 volt),Is that right?

also antenna through L1 connected to ground,as a result,The shield and antena Are connected,Is that right?

Thank you so much.

The important thing is that touching the antenna the signal at the output (TR5 emitter) changes, usually decreases.
The antenna is connected to ground through L1, therefore only to direct current, while for RF signals it must cross an impedance, so it is not true (and should not be) that shielding and antenna are connected together.

[afshin]

Thanks dear franco
When I adjust threshold then the led goes slowly to be on and l have to adjust threshold again.(there is not enough stability)while there is not self oscillation in circuit.(when I remove crystal the output voltage is 0 volt).what is that reason in your opinion?

[FrancoItaly]

Originally Posted by afshin

Thanks dear franco
When I adjust threshold then the led goes slowly to be on and l have to adjust threshold again.(there is not enough stability)while there is not self oscillation in circuit.(when I remove crystal the output voltage is 0 volt).what is that reason in your opinion?

The body affects the threshold, bringing the hand closer to the lrl there may be a change in the threshold. If the DC output (TR5 emitter) is stable then everything is ok.

[afshin]

Very thanks mr franco
I measured TR5 emitter voltage, it goes slowly down and is not stable.
What is that reason mr franco?

[FrancoItaly]

Originally Posted by afshin

Very thanks mr franco
I measured TR5 emitter voltage, it goes slowly down and is not stable.
What is that reason mr franco?

The proof of stability must be done outdoors, as there are too many sources of disturbance inside. If the fault persists there is probably a self-oscillation superimposed on the quartz oscillator. If you have made my double-sided PCB (one for the sensor stage), the self-oscillation can occur due to the excessive gain of TR3 / TR4. Change R10 and R12, from 1K to 1.5K and increase the total value of C1 / C2 / C3, put 1pF or more to have about 4-6V on the emitter of TR5.

[toorani]

hi dear franco
-I Detached the quartz ,votage out put is 0 and with Connected quartz ,voltage out put is 5v but with Touching antenna , voltage out put 10mv or 50mv Increases,In your opinion Why increases? and Is this important hess?

-Is the underlayer Must connected to pin - battry? and Is shild must connected to pin - battry?
http://s8.picofile.com/file/83196673...9_20_32_40.jpg

Thank you so much

[FrancoItaly]

Originally Posted by toorani

hi dear franco
-I Detached the quartz ,votage out put is 0 and with Connected quartz ,voltage out put is 5v but with Touching antenna , voltage out put 10mv or 50mv Increases,In your opinion Why increases? and Is this important hess?

-Is the underlayer Must connected to pin - battry? and Is shild must connected to pin - battry?
http://s8.picofile.com/file/83196673...9_20_32_40.jpg

Thank you so much

When you touch the antenna output voltage must change, usually it decreases, but the important thing is that there is a change and this means that all the sensor stage is ok.
If there is not change it's possible that the stage is self oscillating or the stage works with overload (to much gain).

Pin - battery must be connected to sensor stage ground (upper side) and to shield (lower side of PCB)

[afshin]

Very thanks mr franco
And three questions:
1-Is it may that the ambient temperature affects the threshold stability?
2-what is the advantage of double side circuit comparatively to the one side?
3-what is the best voltage for output of the sensor stage?(TR5 emitter)

[toorani]

Originally Posted by FrancoItaly

When you touch the antenna output voltage must change, usually it decreases, but the important thing is that there is a change and this means that all the sensor stage is ok.
If there is not change it's possible that the stage is self oscillating or the stage works with overload (to much gain).

Pin - battery must be connected to sensor stage ground (upper side) and to shield (lower side of PCB)

hi dear franco
Should the box shield be connected to the pin- battery too?

[FrancoItaly]

Originally Posted by afshin

Very thanks mr franco
And three questions:
1-Is it may that the ambient temperature affects the threshold stability?
2-what is the advantage of double side circuit comparatively to the one side?
3-what is the best voltage for output of the sensor stage?(TR5 emitter)

1- threshold stabilityt is very little influenced by the ambient temperature. This is because the
DC amplification is not very high.

2- the advantage of double side PCB is that the lower side is a shield that prevents self
oscillating.

3- the best voltage for output is in the range 3 - 6V. This voltage depends on gain sensor
stage (TR2/TR3/TR4) and on signal amplitude of quarz oscillator (C2/C3/C4) and there are
many combinations that determine the same output voltage. For example I could have a
signal of 2mv at the base of TR2 and a gain of 3000 and then a signal at the output of 6V
or a signal of 1mV and a gain of 4000 with output of 4V. In the second case we have a
lower output signal but a greater gain (a condition that is preferable).

[FrancoItaly]

Originally Posted by toorani

hi dear franco
Should the box shield be connected to the pin- battery too?

box shield must be connected to pin-battery or to ground PCB (sensor stage or power stage)

[toorani]

Originally Posted by FrancoItaly

box shield must be connected to pin-battery or to ground PCB (sensor stage or power stage)

So Antena is connected to Box Shield,Is that right?

[FrancoItaly]

Originally Posted by toorani

So Antena is connected to Box Shield,Is that right?

NO the Box shield is connected to ground= pin - battery, antenna is connected to L1/C9/10 not to ground, if you connects antenna to ground also the phenomenon goes to ground and you have no usefull signal at output.

[toorani]

Originally Posted by FrancoItaly

NO the Box shield is connected to ground= pin - battery, antenna is connected to L1/C9/10 not to ground, if you connects antenna to ground also the phenomenon goes to ground and you have no usefull signal at output.

hi dear franco
I mean, Antenna connected to the Box shield through L1,Is that right?(Conductively Are connected)
http://uupload.ir/files/owfh_capture.png
http://uupload.ir/files/08rl_photo_2...2_18-18-13.jpg

[afshin]

Thanks mr franco
Is the lower side of the double side PCB connected to the ground of the circuit or not?

[FrancoItaly]

Originally Posted by toorani

hi dear franco
I mean, Antenna connected to the Box shield through L1,Is that right?(Conductively Are connected)
http://uupload.ir/files/owfh_capture.png
http://uupload.ir/files/08rl_photo_2...2_18-18-13.jpg

Yes you can also consider this way, but the fact remains that it is connected to the mass only through L1 and I do not understand why the thing interests you so much.

[FrancoItaly]

Originally Posted by afshin

Thanks mr franco
Is the lower side of the double side PCB connected to the ground of the circuit or not?

Yes the lower side of the double side PCB connected to the ground of the circuit.

[afshin]

Very thanks dear franco to answer my questions and other members.

Best regards

[Merlin]

Sir FrancoItaly, Thanks for your LRL!
You are a good man!
I decided to make this your LRL - Sensor:







And this is my PCB:


Final appearance without Quartz:



However, I have a problem!
The voltage on the R5 Emiter is 6.09V without the mounted Quartz.
When I R1 sampled from 33K to 27K - the voltage is stable 5.27V.
The same voltage is when I mount the Quartz, however, the voltage is not reduced when I touch the antenna input.
Please help me with a voltage of 0V!
What should I do???
In advance, thank you very much for your reply!
Merlin

[FrancoItaly]

Originally Posted by Merlin

Sir FrancoItaly, Thanks for your LRL!
You are a good man!
I decided to make this your LRL - Sensor:







And this is my PCB:


Final appearance without Quartz:



However, I have a problem!
The voltage on the R5 Emiter is 6.09V without the mounted Quartz.
When I R1 sampled from 33K to 27K - the voltage is stable 5.27V.
The same voltage is when I mount the Quartz, however, the voltage is not reduced when I touch the antenna input.
Please help me with a voltage of 0V!
What should I do???
In advance, thank you very much for your reply!
Merlin

Maybe you did not read what I had written on the PCB, the components must be soldered from the copper side (as smd) and it would be advisable to use a double-sided PCB with the bottom face connected to the ground as a screen. Your PCB can not work (if you have perfectly copied mine) because for example the emitter / collector pins of all transistors are inverted.

[Merlin]

Originally Posted by FrancoItaly

Maybe you did not read what I had written on the PCB, the components must be soldered from the copper side (as smd) and it would be advisable to use a double-sided PCB with the bottom face connected to the ground as a screen. Your PCB can not work (if you have perfectly copied mine) because for example the emitter / collector pins of all transistors are inverted.

Thanks for your reply sir FrankoItali!
I will make the PCB as you suggest, so I will place the result here on the forum.
I hope it will work.
Please - just one more question:
I do not understand whether it's a mistake or not, but on your assembly scheme, the C5 and C7 сapacitors are labeled as electrolytic, and this is not the case in the circuit diagram.
My question is:
- What are the condensers: ceramic, block, tantalum or electrolytic?
I am very grateful for your response in advance!
Merlin

[FrancoItaly]

Originally Posted by Merlin

Thanks for your reply sir FrankoItali!
I will make the PCB as you suggest, so I will place the result here on the forum.
I hope it will work.
Please - just one more question:
I do not understand whether it's a mistake or not, but on your assembly scheme, the C5 and C7 сapacitors are labeled as electrolytic, and this is not the case in the circuit diagram.
My question is:
- What are the condensers: ceramic, block, tantalum or electrolytic?
I am very grateful for your response in advance!
Merlin

C5/C7 are ceramic as other capacitors, only C6/C8 are electrolytic.

[abdou2014]

I made my latest version of franco LRL with some modification, and I had different results, this version does not react to the television or the electric devices, except that is very sensitive to the FM waves , I try them with a small FM transmitter and it detect it to ten meters, I want to have the opinion of Franco on these results?

[FrancoItaly]

Originally Posted by abdou2014

I made my latest version of franco LRL with some modification, and I had different results, this version does not react to the television or the electric devices, except that is very sensitive to the FM waves , I try them with a small FM transmitter and it detect it to ten meters, I want to have the opinion of Franco on these results?

I think the answer can only be found on a real field.