Lrl from Italy

[zixelll]

Hi Franco, I did not understand what you meant. Should you have mkt for this capacitor?

[FrancoItaly]

Hi Franco, I did not understand what you meant. Should you have mkt for this capacitor?

you did not ask for a capacitor, I struggle to understand what you say.

[zixelll]

The ceramic capacitor is suitable for this circuit, or the capacitor mkt

[zixelll]

Hello Franco I live in Iran. How much frequency should I set up my device and put the battery in the handle?

[FrancoItaly]

The ceramic capacitor is suitable for this circuit, or the capacitor mkt

ceramic capacitor is suitable for this circuit

[FrancoItaly]

Hello Franco I live in Iran. How much frequency should I set up my device and put the battery in the handle?

No frequency set up is necessary and the battery case is no critic.

[maziio]

Thanks for answering

This answer is for maziio, that sent me a private message but I can not answer him:

I have simulated with multisim and the sensor stage works with BC183C or BC183B or equivalent but obviously it is not possible to simulate it completely. Essentially the sensor stage is composed of a high gain amplifier (TR2-TR3-TR4) that amplifies a small part of the signal coming from the 8Mhz oscillator and that is what can be simulated. The "heart" of the lrl is centered on TR2, where the mixing between the 8Mhz signal and the signal coming from the antenna takes place. The main difficulty is to prevent the whole sensor stage from becoming an oscillator and at the same time having a good amplification. On the forum there are some PCBs posted by members that include the whole lrl. In my opinion it is better a separate PCB for the sensor stage, better if double-sided and this is what I did.

Best Regards

Hi Dear Franco
I have done simulation with proteus and it is OK but I want to know about the display stage that doesn't work.according to datasheet of lm358 I have found that it works with a +-16 or 32 volts but in this way of connection I do not know how this stage works with that power supply and secondly how much voltages is on led`s and how could be the signal in there
and the crystal is not putted correctly for oscillation.(please tell me that how much voltage must be on out part of sensor stage and the led`s to +12 while they are connected to out of lm358 .

[FrancoItaly]

Hi Dear Franco
I have done simulation with proteus and it is OK but I want to know about the display stage that doesn't work.according to datasheet of lm358 I have found that it works with a +-16 or 32 volts but in this way of connection I do not know how this stage works with that power supply and secondly how much voltages is on led`s and how could be the signal in there
and the crystal is not putted correctly for oscillation.(please tell me that how much voltage must be on out part of sensor stage and the led`s to +12 while they are connected to out of lm358 .

You're right, the reason is that I did not point to the LM358's power legs, in the Dream.man scheme they are shown correctly. The output of the sensor stage is in the 4-6V range and the quartz oscillator oscillates equally without the second capacitor thanks to the parasitic capacities and it seems to me that when I posted the project I said to add the condenser if the oscillator had not It worked. However I built 10 copies of this lrl and the quartz has always oscillated.

[zixelll]

Franco you confirm this schematic to build?

[zixelll]

Dream_Man - 8MHz - Quartz LRL Sensor Stage %2B Power Stage with Low Battery Indicator %2B Displ.PDF

[FrancoItaly]

[ATTACH]20137[/ATTACH]

Yes, this is the PCB:

[zixelll]

Are you confirming Franco pcb?

[zixelll]

Do you think this pcb has a problem?

[FrancoItaly]

Are you confirming Franco pcb?

This is not mine.

[zixelll]

Yes, you have a friend, so you confirm this design?