Lrl from Italy

[liudengyuand]

For so many years, I haven’t seen you make a decent pcb. A decent machine. I haven’t seen you make a video. You don’t even know the value of the inductance. What tuning are you talking about?

[FrancoItaly]

In Italy there is a proverb "appearances are deceiving".

[liudengyuand]

Let me tell you the truth, this circuit is made of double-sided copper clad laminate, and the output is only a little bit. When made of single-sided copper clad laminate, the output is more than two volts. It does not matter how much the output is. As long as it can be compared in the end, there is no adjustment for l1 and c10. Meaning, within the range of 100pf, or even greater, its sensitivity has not changed much. It can react to the sky or some ground, but this is only a problem of geographic magnetic field and has nothing to do with metal. Don’t say you succeeded. In fact, no one has ever seen you, nor can you know that you succeeded or failed. You always like to hear others say that you succeeded, and you hate others to say no. This is your psychological problem. You found water at a depth of 60 meters in your country. The basic knowledge tells you that as long as it is not a mountain, there is basically water in the ground 60 meters deep. You attribute this function to the oc

[FrancoItaly]

All forum members will take note of your opinion, as far as I'm concerned I have nothing more to say to you.

[Rubin]

Hello Franco
You write:
We cannot use an oscilloscope for measurements in the sensor stage and for the adjustment need only one voltmeter is required to connect to the output of the filter R16, C18 without the use of the oscillator.
If we have 2-4volts DC output, this means that the sensor stage is working properly without oscillations.
But .... we can have oscillation, because a voltmeter can not show it and let us have an output in the range 2-4v DC
My question.
Can we use the oscilloscope to properly adjust the trimmer on the TR3 emitter or is it practically setting in the field?
Please explain more
Thank you

[FrancoItaly]

Originally Posted by Rubin

Hello Franco
You write:
We cannot use an oscilloscope for measurements in the sensor stage and for the adjustment need only one voltmeter is required to connect to the output of the filter R16, C18 without the use of the oscillator.
If we have 2-4volts DC output, this means that the sensor stage is working properly without oscillations.
But .... we can have oscillation, because a voltmeter can not show it and let us have an output in the range 2-4v DC
My question.
Can we use the oscilloscope to properly adjust the trimmer on the TR3 emitter or is it practically setting in the field?
Please explain more
Thank you

in the helps I wrote: "For the first test do not connect quartz then look at out point, the DC voltage must be 0V.". The sensor stage output is always a DC voltage, rectified by the two diodes. This voltage is the rectified 8Mhz signal. The use of the oscilloscope is only for verifying the proper functioning of the oscillator. Outdoors there is no need for any adjustment other than the threshold and gain in the stage display.

[Rubin]

Thanks for your quick reply.
After checking I saw that. With the trimmer calibration min-max in the emitter TR3 the output to the filter is not 0V DC (without oscillator), but output is 50mv-150mv. So i think we cannot have 0V DC because the diodes produce this increase signal
Ofcourse (without oscillator, coil and antenna) if we touch the input, the output is >8V DC. This is correct?
I repeat again i use only sensor stage without oscillator coil and antenna

[brs]

Originally Posted by liudengyuand

Let me tell you the truth, this circuit is made of double-sided copper clad laminate, and the output is only a little bit. When made of single-sided copper clad laminate, the output is more than two volts. It does not matter how much the output is. As long as it can be compared in the end, there is no adjustment for l1 and c10. Meaning, within the range of 100pf, or even greater, its sensitivity has not changed much. It can react to the sky or some ground, but this is only a problem of geographic magnetic field and has nothing to do with metal. Don?t say you succeeded. In fact, no one has ever seen you, nor can you know that you succeeded or failed. You always like to hear others say that you succeeded, and you hate others to say no. This is your psychological problem. You found water at a depth of 60 meters in your country. The basic knowledge tells you that as long as it is not a mountain, there is basically water in the ground 60 meters deep. You attribute this function to the oc

He gave Franco everything he had. Thanks Franco. As for you, you just have to criticize others.

[zakari]

hi franco

thank you so much for sharing this circuit

i made several time your lrl that is work perfect

best regard

zakari

[zakari]

hi
i used china digital fm transmitter module and injecte weak signal from transmitter to base of tr2 ,i have removed xtal and tr1 i have nulled transmitter and reciever antenna's
that is working good
now i can change the transmitter frequence and tune in my area for best operation
best regard

zakari

[FrancoItaly]

Originally Posted by zakari

hi
i used china digital fm transmitter module and injecte weak signal from transmitter to base of tr2 ,i have removed xtal and tr1 i have nulled transmitter and reciever antenna's
that is working good
now i can change the transmitter frequence and tune in my area for best operation
best regard

zakari

What you did is very interesting, did you keep L1 / C10? If so, have you tuned the transmitter frequency with L1 / C10? I too am experimenting with an FM oscillator that I made, my problem is that the signal is always too strong and saturates the sensor stage, I have tried unsuccessfully to shield the oscillator and further decouple the oscillator power supply.