Lrl from Italy

[FrancoItaly]

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]

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]

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]

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]

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_2018-03-12_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]

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]

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]

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]

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]

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]

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.