Lrl from Italy

[FrancoItaly]

In my opinion it is not possible in fact even by connecting an oscilloscope the signal is interrupted.

[omar]

[QUOTE=Inna;162126]Hi Omar, I realize only now that in your pcb C6 and C8 (electrolytic capacitors) are marked with a value of 10 uF, while on the diagram, Mr. Franco puts them at 100 uF, I wanted to confirm if this is a writing error. Thank you


Hi my friend these capacitors are to smooth the current. Put what you see fit. I ask you to view this blog to understand more about some things, as it is similar to the Franco device.

http://techlib.com/electronics/allband.htm

[FrancoItaly]

The circuit is interesting, but I have some doubts about the values of 10M and 100k, they seem too high for bipolar transistors.

[sweker]

this is the last design for franco lrl

[FrancoItaly]

The antenna seems too short, I recommend in the 30-40cm range, increasing the length of the antenna increases the sensitivity and vice versa.

[sweker]

MR FRANCO CAN YOU please put full pdf descriptions of 20 mhz version

[FrancoItaly]

Remember that I have created 3 20Mh lrls and only the first one works well, therefore I cannot provide assistance because I did not understand what the problem was with the 2 non-functioning lrls. However it is important to make a pcb only for the sensor stage.

[sweker]

Remember that I have created 3 20Mh lrls and only the first one works well, therefore I cannot provide assistance because I did not understand what the problem was with the 2 non-functioning lrls. However it is important to make a pcb only for the sensor stage.

MR Franco I have three questions thankfully
1. can I use stable power supply 12v instead your18 v power stage?
2. does the display stage work probably with stable power supply 12v ?
3. what Is the value of P 2 in the new display stage ..is it 1 M ?
thank you so much

[FrancoItaly]

All my lrl runs on stabilized 12V and since the stabilizer IC requires at least 15V (12V + 3V) to work properly I used two 9V batteries. Any other system that supplies stabilized 12V is fine.
Potentiometer P2 is 1M.

[sweker]

All my lrl runs on stabilized 12V and since the stabilizer IC requires at least 15V (12V + 3V) to work properly I used two 9V batteries. Any other system that supplies stabilized 12V is fine.
Potentiometer P2 is 1M.

Hello again MR FRANCO ,Did you use two separate pcb for sensor stage of 20 Mz as you mention in the help paper (the 20Mz oscillator has 2 transistors and various additional components, therefore it will have to be made on a separate pcb )

[FrancoItaly]

There isn't an extra transistor, if you only have one pcb for everything you can try it like this, it might even work, I have no experience on this, I always used two pcb.

[sweker]

There isn't an extra transistor, if you only have one pcb for everything you can try it like this, it might even work, I have no experience on this, I always used two pcb.

20 Mhz components - helps (2).txt
MR Franco Honestly I did not understand the steps of adjusting the device to prevent self oscillation , could you please write it in steps or give me voice instruction step by step

[FrancoItaly]

I'm sorry, but I warned on the forum that I couldn't help to build the 20Mhz lrl, because only the first lrl works, but the following two don't, probably the project is too critical. Also my English is written only.

[sweker]

I'm sorry, but I warned on the forum that I couldn't help to build the 20Mhz lrl, because only the first lrl works, but the following two don't, probably the project is too critical. Also my English is written only.

MR FRANCO at the testing stage as you said do not connect the quartz then test the voltage at the out , which out do you mean to be measured?

[FrancoItaly]

I briefly summarize the operation, the sensor stage amplifies the oscillator signal which must be very small otherwise the sensor stage is saturated, in the mixer TR2 the mixing of the oscillator signal and the "phenomenon" takes place. Removing the crystal, therefore without oscillation, the output must be 0, if there is a DC signal it means that the whole sensor stage auto oscillates, an undesirable condition because putting the crystal would have a low sensitivity. Then decrease the amplification until the output is zero, this can be done by decreasing C13/C/14.