Lrl from Italy

[taxma1981]

with bc 547c work fine

[taxma1981]

I need antenna and ist ok

[taxma1981]

https://youtu.be/uCezifFu8Ss

[taxma1981]

Detect microwave why?

https://youtu.be/vAr6ByPwkn0

[FrancoItaly]

The resonant circuit connected to the antenna is in the range 100-150Mhz and sources of radio frequency which falls in this range (also with sub harmonics) affect the LRL especially if they are very close and in the house there are many sources of this kind. We can use these sources to test our LRL but my favorite test it's to touch the antenna and check the signal decreases, to do this set the threshold so that the LED is turned on weakly then by touching the antenna the led should go off.
Regards

[taxma1981]

I did this when handling the antenna, the voltage drops .. Detects static Yesterday rubbed the comb in the hair of 4 meters and started beating

[taxma1981]

how crystal is working better franko ?we can be put and largest;

[FrancoItaly]

If you mean the size of quartz, small size is equal to normal size. The frequency is no critic, I have used 4 - 6 - 8 and 10Mhz with no difference.

[taxma1981]

Frank 4-6 volts must have; measuring the exit to ground; so why zero .... 4-6 volts only shows measuring the exit and entrance front

[FrancoItaly]

I don't understand what you mean with "zero", the DC output of sensor stage, that's the rectified AC signal, it must be in the range 2-6V.

[FrancoItaly]

For Saromines_R and for others who have asked for my help.
if on the emitter of TR5 there is a voltage equal to or greater than 7V:

1)- remove C2, C3 and C4 and measure voltage again, it is still higher than 7V, decrease the value of C13 (from 560pF to 470pF or 330pF) if not enough reduce also C14. Reconnect C2, C3 and C4, if the output is between 2 and 6V LRL is ok but if it is still high, go to point 2:

2)- Try for C2 0.5pF or less

3)- remove C2, C3 and C4 and try the connection with two wires which it is equivalent to a capacitor of very low capacity. You can also twist the two wires to vary the capacity.

4)- try the connection with one wire which it is equivalent to a little antenna, start with a length of 10cm and try different solutions, passing near the base of TR2 and possibly shortening if the voltage is still too high.

I hope this can help, if you can not get the right voltage then you need to redesign a new pcb, preferably double-sided with one side connected to ground.

[taxma1981]

here measured Franco; the exit of the way 5, and in front of the entrance of TP1;

[FrancoItaly]

I don't understand, what is TP1, transistor TR1? What 's the voltage at TR5 emitter? If you have 2 - 6V and when you touch the antenna the voltage drops it's all OK.

[taxma1981]

the proposal does not fall Touching the antenna.

[RS_Phil]

Thanks sir Franco...