Tribute to Andy Flind

[Geo]

Originally Posted by Esteban

Horizons? All detectors are affected by magnetic field of Earth. When you have adjusted excluding it, well the difference is another cause, almost always metal buried many years. Of course, you can use a kind of dish connected to - , but you must found distance between dish and coil.

I modificate the old I have, but now with preamp. Look shielded cables in input, potentiometer and main PCB input. Also you can try shielding the core or the coil, deppend what you use. I use core and aluminum loop.

Regards

Thank you Esteban.
I must try another coil so to have the ability to shield it.
Now the coil has diameter about 10 cm. Who is your opinion??? to winding a biger coil or no.

Regards

[FrancoItaly]

Hi Geo
With my pistol, oscillator coil (a square of 25 cm) at 135 Khz, rx stage with more then 100M of impedance, no motion stage with push button retune, I sense a charged plastic rod at more then 2 m and a tree at 1 m and a stone wall at 80 cm, but I don't have a test target. The next week I will test my instrument near an old castle. My design is not similar to Morgan pistol, the sensor is a squared printed board of 5 cm, the amplification of rf stage is about 80 and after I rectify the signal.
Best Regards

[Esteban]

Originally Posted by Geo

Thank you Esteban.
I must try another coil so to have the ability to shield it.
Now the coil has diameter about 10 cm. Who is your opinion??? to winding a biger coil or no.

Regards

I'm finish another MFD with 16 cm coil. I'll post here results of it. But with core and aluminium loop also at 23 hour (I test the last night) detect very well, better the couple of "green" coins in pile buried 15 years ago than stainless-steel gold platted clock buried 16 years.

[Esteban]

Originally Posted by Alexismex

"but when they were upon the second one, the oscillator transistors got burned due to the intense fields"
What a big treasure !!! to kick *** the transistors, like e EMP from atomic bomb explosion !!!!
Make me laugh again, this thread is a delicatessen sensation for me and a positive enlightment for the technical forum....

Treasure knock (or destroy) fet input IC as CA3130 when his input is connected to antenna.

[aft_72005]

Originally Posted by FrancoItaly

Hi Geo
With my pistol, oscillator coil (a square of 25 cm) at 135 Khz, rx stage with more then 100M of impedance, no motion stage with push button retune, I sense a charged plastic rod at more then 2 m and a tree at 1 m and a stone wall at 80 cm, but I don't have a test target. The next week I will test my instrument near an old castle. My design is not similar to Morgan pistol, the sensor is a squared printed board of 5 cm, the amplification of rf stage is about 80 and after I rectify the signal.
Best Regards

Hi Francoitaly

Congratulate .
I am interesting to your test result in real field .
Best regards.

[WM6]

Originally Posted by Esteban

Treasure knock (or destroy) fet input IC as CA3130 when his input is connected to antenna.

Esteban, this is not treasure that cause knocking. You are attacked by woodoo magia. May helped if you use your device without battery.

[detectoman]

geo: you lrl is so sensitive, these is good, but north and shout alteracion is normal, you should go always north-south how morgan say, if very sensitive modify the coil more less turns, put wire gross most stability, this all

[detectoman]

geo: not put big metal iron near the coil, for best , shield any sensitive transistor, regulate ok the voltage whit little set pot, put indicator of voltage of neddle, in current function, equal to little, the circuits whit preset resistences, but not destroy any lrl stable, only modify litle to little, and whit caution

[Geo]

Originally Posted by FrancoItaly

Hi Geo
With my pistol, oscillator coil (a square of 25 cm) at 135 Khz, rx stage with more then 100M of impedance, no motion stage with push button retune, I sense a charged plastic rod at more then 2 m and a tree at 1 m and a stone wall at 80 cm, but I don't have a test target. The next week I will test my instrument near an old castle. My design is not similar to Morgan pistol, the sensor is a squared printed board of 5 cm, the amplification of rf stage is about 80 and after I rectify the signal.
Best Regards

Hi FrancoItaly.
My pistol works also at 135 Khz. My detector don't detects the trees and the stones but i have not yet good results with buried objects. The receiver coil is a round 10 cm. It has excellent sensitivity but .... nothing yet. Or maybe i detect at wrong place .
My receiver has more than 1000 gain until to rectifier.


Regards

[Geo]

Originally Posted by Esteban

I'm finish another MFD with 16 cm coil. I'll post here results of it. But with core and aluminium loop also at 23 hour (I test the last night) detect very well, better the couple of "green" coins in pile buried 15 years ago than stainless-steel gold platted clock buried 16 years.

Hi Esteban.
If it detect better the "green" coins then i like it. Do you sell it ?????
What is the small switch at the side of the box?? As i see it go at the common point of leds. These days i will winding a mono shielding coil for my detector so to see what is happening with the horizons....

Regards

[Geo]

Originally Posted by detectoman

geo: you lrl is so sensitive, these is good, but north and shout alteracion is normal, you should go always north-south how morgan say, if very sensitive modify the coil more less turns, put wire gross most stability, this all

Hi detectoman.
Yes i must go from north to south but if it detect all the 4 horizons then i can't move the pistol more than 60 degrees. It is not workable, and you can't always to go from north to south......
What are you meen when you say to put wire gross????
My detector is very stable, maybe with the coil shielding to solve the problem. I work far from electric lines so i think that it is not need to shield every sensitive unit.

Regards

[FrancoItaly]

Hi Geo
I don't have a receive coil, with this coil you sense mainly a change in magnetic field. I have only a small pcb that acts as voltage sensor. I have as reference the successive models of Mineoro that don't have a receive coil and not even a sort of Induction Balance coil.
Best Regards

[Esteban]

Originally Posted by Geo

Hi Esteban.
If it detect better the "green" coins then i like it. Do you sell it ?????
What is the small switch at the side of the box?? As i see it go at the common point of leds. These days i will winding a mono shielding coil for my detector so to see what is happening with the horizons....

Regards

I "prepare" the green coins (verdigris). I describe it in another thread. Is better bury it in pile as Volta battery than sparzed... another discovery. The "column of ions" or "phenomenon" is detected near + - 1 m over the target.

Regards

[Geo]

Originally Posted by FrancoItaly

Hi Geo
I don't have a receive coil, with this coil you sense mainly a change in magnetic field. I have only a small pcb that acts as voltage sensor. I have as reference the successive models of Mineoro that don't have a receive coil and not even a sort of Induction Balance coil.
Best Regards

Hi FrancoItaly.
Ohh.. you remembered me a previous model where i had only a coil for transmitter and the tuning was via a buton and a LF398. This detector was very sensitive to trees .. stones etc. No good... but i wish your LRL to be better.

Regards

[Geo]

Originally Posted by Esteban

I "prepare" the green coins (verdigris). I describe it in another thread. Is better bury it in pile as Volta battery than sparzed... another discovery. The "column of ions" or "phenomenon" is detected near + - 1 m over the target.

Regards

Hi Esteban.
At who thread did you wrote about the preparation of "green" coins???
Today i went to another place. Pistol gave me some beeps (but no continuant). If tomorrow afternoon is not raining i will go again with my metal detector so to check the place.

What about "small switch"??

Regards

[WM6]

Originally Posted by Esteban

The "column of ions" or "phenomenon" is detected near + - 1 m over the target.

Yes, but only if you know where the target is buried, otherwise it does not appear "column of ions" or "phenomenon".

[detectoman]

geo: for experence, in lrl, very thickness wire is most sensitive, but unstable, not thicknes is less sensitive but stable, coil big is stable, coil little less stable, oval coil discriminate major, square coil is good for put out noises, stable, coil glued is stable coil not glued very unstable to vibrations or warm, coil inside wood is good, whit paint white, coil inside black plastic unstable etc coper aleate hard good for tx coper soft good for rx etc, lrl is minuciosa science
lrl isnt for standar people without patiente, is for obsesive builders
lrl is science whit very much distincts metod, what is major? simple is major

[FrancoItaly]

Hi Geo
Your receive coil is induction balanced ? Or it's a single turn coil and then it's a sort of antenna ? In my instrument I can detect positive signals with green led and a beep and negative signals with a blue led and no beep. Trees and walls cause negative signals. Perhaps I have to realize a sort of discrimination or ground exclude but my test with a synchronous demodulator or a phase comparator it reveals no phase change between trees and my charged plastic rod. I think that it'is no a great disadvantage the sensibility to trees and walls if I am almost 1 meter away.

Best Regards

[Esteban]

Originally Posted by WM6

Yes, but only if you know where the target is buried, otherwise it does not appear "column of ions" or "phenomenon".

You know where is the target at some meters, so, you can study "phenomenon".

[Esteban]

Originally Posted by Geo

Hi Esteban.
At who thread did you wrote about the preparation of "green" coins???
Today i went to another place. Pistol gave me some beeps (but no continuant). If tomorrow afternoon is not raining i will go again with my metal detector so to check the place.

What about "small switch"??

Regards

You don't need to use hundreds bronze and nickel coins. Maybe 20 is OK, but better as Volta battery disposition. You can use transparent common tape for paper for to keep the form and it will not move when is bury. 20-25 cm depth is OK.

http://www.geotech1.com/forums/showthread.php?t=15408

[Esteban]

New design

[Geo]

Originally Posted by Esteban

You don't need to use hundreds bronze and nickel coins. Maybe 20 is OK, but better as Volta battery disposition. You can use transparent common tape for paper for to keep the form and it will not move when is bury. 20-25 cm depth is OK.

http://www.geotech1.com/forums/showthread.php?t=15408

Thank you Esteban.
With "Volta battery disposition" do you mean each coin on the other.... one bronze, one nicel ... etc???

Regards

[Geo]

Originally Posted by Esteban

New design

What LRL is this???? Is the MFD in new box??? Did you test it??

Regards

[Geo]

Originally Posted by detectoman

geo: for experence, in lrl, very thickness wire is most sensitive, but unstable, not thicknes is less sensitive but stable, coil big is stable, coil little less stable, oval coil discriminate major, square coil is good for put out noises, stable, coil glued is stable coil not glued very unstable to vibrations or warm, coil inside wood is good, whit paint white, coil inside black plastic unstable etc coper aleate hard good for tx coper soft good for rx etc, lrl is minuciosa science
lrl isnt for standar people without patiente, is for obsesive builders
lrl is science whit very much distincts metod, what is major? simple is major

Thanks...

[Geo]

Originally Posted by FrancoItaly

Hi Geo
Your receive coil is induction balanced ? Or it's a single turn coil and then it's a sort of antenna ? In my instrument I can detect positive signals with green led and a beep and negative signals with a blue led and no beep. Trees and walls cause negative signals. Perhaps I have to realize a sort of discrimination or ground exclude but my test with a synchronous demodulator or a phase comparator it reveals no phase change between trees and my charged plastic rod. I think that it'is no a great disadvantage the sensibility to trees and walls if I am almost 1 meter away.

Best Regards

Hi FrancoItaly.
No my coil was a simple mono coil connected at the output of a oscillator. If i tune exactly at the center of frequency then i have "negative and positive" signals, or signal from up and down carrier side. I let it because it was very sensitive at people... trees ... stones... but NOT at buried objects

Regards