Lrl from Italy

[JHERICKU]

Hi friend
Looks like something is wrong, but wait for Franco to tell his opinion as he is very experienced on this.


(try connecting your voltmeter at the output of your sensor. When you touch the antenna, does the output signal drops?)

I do not know where to put the test probe to measure the voltage..I have have no idea if it is droping or not..

This time I change te 10k potentiometer with 25k and remove the sensor stage for a while but there is no buzz and led ligths at all..I have noticed that when I touched everywhere on the board the led and buzzer beeps also..I think it is grounded..
Any suggestions my friend..

[FrancoItaly]

I do not know where to put the test probe to measure the voltage..I have have no idea if it is droping or not..

This time I change te 10k potentiometer with 25k and remove the sensor stage for a while but there is no buzz and led ligths at all..I have noticed that when I touched everywhere on the board the led and buzzer beeps also..I think it is grounded..
Any suggestions my friend..

The point to be measured is the output of the sensor stage, the one that goes to the input of the display stage. For the rest I don't know what to say, check the assembly carefully, maybe you made some mistakes.

[JHERICKU]

hello friend franco,Should I connect the negative probe of the multimeter to ground and the positive one to antenna to get the reading or the positive probe to transistor 04 emitter ?

I am so sorry..I have few knowledge about electronics..My apologies..

[JHERICKU]

The point to be measured is the output of the sensor stage, the one that goes to the input of the display stage. For the rest I don't know what to say, check the assembly carefully, maybe you made some mistakes.

I put the probe on sensor output and I got 4.+volts. I touched the antenna and the voltage is thesame..why should I do?

[FrancoItaly]

hello friend franco,Should I connect the negative probe of the multimeter to ground and the positive one to antenna to get the reading or the positive probe to transistor 04 emitter ?

I am so sorry..I have few knowledge about electronics..My apologies..

The negative probe of the multimeter to ground and the positive to transistor 04 emitter.

[JHERICKU]

The negative probe of the multimeter to ground and the positive to transistor 04 emitter.

I got 1.5 volts on transistor04 emitter with the trimmer on maximum..I have noticed that it beeps when I touched the board or the potentiometer and the antenna but the output not dropping..I believed the antenna is on positive line.It gives me 12v measurement..

[JHERICKU]

I remove the quartz and I got .044 volts on output..Can anyone have idea especially to franco if I got the correct output?
ps.I used 4mhz quartz..
Thank u for suggestions in advance..

[Rubin]

I would like to know who knows or has tested, if the franko circuit can detect nuggets.
I ask, because i have many signals from a place and i find only small nuggets.
I am comfused

[FrancoItaly]

I remove the quartz and I got .044 volts on output..Can anyone have idea especially to franco if I got the correct output?
ps.I used 4mhz quartz..
Thank u for suggestions in advance..

The sensor stage output measurement is on the emitter of TR5, not TR4.

[FrancoItaly]

I would like to know who knows or has tested, if the franko circuit can detect nuggets.
I ask, because i have many signals from a place and i find only small nuggets.
I am comfused

In theory, if the nuggets have been in that place for long enough, they should generate the phenomenon. The unknown is the size, I don't know if so small they emit a sufficient signal. The other explanation is that there are metals buried deeper than the range of the MDs and this may have happened in your case.

[Jeg]

I don't know if so small they emit a sufficient signal.

Obviously they do emit such a signal as rubin found them and your receiver can get it.

Rubin, what is the distance approximately that you hit them, and what is your crystal's frequency if you don't mind?

[Rubin]

Obviously they do emit such a signal as rubin found them and your receiver can get it.

Rubin, what is the distance approximately that you hit them, and what is your crystal's frequency if you don't mind?

With 8mHZ crystal the distance is 3 meters. With 16MHz crystal the distance is shorter
The spot has small stones with nuggets.
I do not know what is happening, so I asked if anyone has tried to let me know

[Jeg]

With 8mHZ crystal the distance is 3 meters. With 16MHz crystal the distance is shorter

Great observation Rubin. Thank you.
I wonder if a 1Mhz can increase this distance more.

[JHERICKU]

Hello to all..I got 4.706volts on tr05 emitter..when I touched the antenna,the voltage doesnt drop but increases to 4.711volts instead..Anyone can advice me..especially to franco..thank u in advance..

[FrancoItaly]

Hello to all..I got 4.706volts on tr05 emitter..when I touched the antenna,the voltage doesnt drop but increases to 4.711volts instead..Anyone can advice me..especially to franco..thank u in advance..

Touching the antenna is a test to determine if the sensor stage amplifies, if the signal increases instead of decreasing I don't think it's a problem, the real test is on the ground.