postLRL circuit for coin at two meter

[Esteban]

Hi estabn,
Thanks for information.Looks interesting.
Perhaps you could also use tuned loops antennas as like in VLF reception,they have narower bandwith so yo pick up less noise?
Can you say that detection wit such devices is really reliable, or if there is always some erratic noises so you cannot be sure if it is really working 100%.?
Regards,
Fred.

Near strong electromagnetics emission like TV, HV lines, etc., this isn't reliable, but in sites more quiet, OK. Treasure "can't scape" of this at 20-30 meters and big silver coin can be detected 3 m. but not sustain the detection for long time, for small items.

Regards

Esteban

[Max]

For short distance (few meters) I use a closed aluminium loop. I'll detect good conductive items as silver and copper coins with it, some gold, bronze, etc. If you increases ohms in ferrite, you'll detect more trash, at this time I don't detect aluminium can beer, fo example. This is pure receiver. The loop you see here is part of the project I'll post here as "Treasure detector". If there are a treasure in vecinity of the device, sure you'll detect it, except if is inside closed iron box. But don't know if can detect oxidated iron box, maybe...

You can detect a treasure with a simple cassette recorder used by journalists. You dismantle the magnetic head and mount this loop system instead magnetic head. (Select the input with more gain, because always stereo has one more sensitive input.)

But I'll design one based on dual amplifier, like stereo, with 2 sensors and 2 sensibility controls, for each sensor.

Hi,
the "core" seems a toroid of ferrite with wounded coil upon it, right ?

From what I understand there's a magnetic coupling from any local to toroid magnetic field line generated by current in aluminium loop.

This is like happens in some aluminium antennas with kind of magnetic transformer for impedance matching there with receiver... aluminium structure is "tuned" to a specific frequency or range of frequencies (but this is not good for broadband antenna things) and then transformer get signals for receive by just induction.

The problem is... what causes the current flow in the aluminium loop in this case?

I mean... if you move the al-turn in the Earth magnetic field... you can get voltage variations due to variation of coupling between the turn and the field.

But if you hold it fixed in one position the only thing that could induce current in it is cause of some external RF emission.

But which RF emission ??? From target ???

I do not understand this.

Kind regards,
Max

[Esteban]

Hi,
the "core" seems a toroid of ferrite with wounded coil upon it, right ?

From what I understand there's a magnetic coupling from any local to toroid magnetic field line generated by current in aluminium loop.

This is like happens in some aluminium antennas with kind of magnetic transformer for impedance matching there with receiver... aluminium structure is "tuned" to a specific frequency or range of frequencies (but this is not good for broadband antenna things) and then transformer get signals for receive by just induction.

The problem is... what causes the current flow in the aluminium loop in this case?

I mean... if you move the al-turn in the Earth magnetic field... you can get voltage variations due to variation of coupling between the turn and the field.

But if you hold it fixed in one position the only thing that could induce current in it is cause of some external RF emission.

But which RF emission ??? From target ???

I do not understand this.

Kind regards,
Max

Hi, also Idon't know exactly what happens, what kind of emission can exist, but in general you move the antenna slowly for to cause a kind of AC variation.

Regards

Esteban

[Max]

Hi, also Idon't know exactly what happens, what kind of emission can exist, but in general you move the antenna slowly for to cause a kind of AC variation.

Regards

Esteban

Hi,
so the coil must be moved to detect signal...
if you move the coil slowly you can get signal from a variation of flux related to Earth magnetic field. This is similar to magnetometers when the EMF is sampled or read with continuity to get the logs and then find if there's any anomaly in local intensity.

Maybe the target changes the field gradient in it's vicinity ? But this will give you readings also on e.g. soft iron targets that have great magnetic permeability.

What do you hear on speaker/headphones when it detects a target ?

Kind regards,
Max

[Dell Winders]

Quote:
And Randy, and some of the other "Pretend" intellectual critical thinkers who patronize geotech forums as gospel, when (IF) you do become open minded about Remote Sensing Discrimination LRL, you will be eating crow for a long time.
Randy,I sincerely apologize. It should have read:

And J_PLAYER, and some of the other "Pretend" intellectual critical thinkers who patronize geotech forums as gospel, when (IF) you do become open minded about Remote Sensing Discrimination LRL, you will be eating crow for a long time. Dell

Randy, I'm sorry! Your name was not intended. The phone was ringing as I was finishing the post.
There are only a few minutes allowed to edit on this forum, and I caught my mistake too late to do any thing about it.

I apologized a few posts later,but apparently you didn't catch it. You are one of the few responsible people who post on this forum, and the reason I even bother to read the posts. Again, I sincerely apologize to you for my typo error. Dell

[Dell Winders]

So little, so late!

Originally Posted by Esteban
Hi, also Idon't know exactly what happens, what kind of emission can exist, but in general you move the antenna slowly for to cause a kind of AC variation.

Regards

Esteban
Hi,
so the coil must be moved to detect signal...
if you move the coil slowly you can get signal from a variation of flux related to Earth magnetic field. This is similar to magnetometers when the EMF is sampled or read with continuity to get the logs and then find if there's any anomaly in local intensity.

Maybe the target changes the field gradient in it's vicinity ? But this will give you readings also on e.g. soft iron targets that have great magnetic permeability.

What do you hear on speaker/headphones when it detects a target ?

Kind regards,
Max

Shhhh! Don't tell Carl. I've been bashed, mocked, and ridiculed by the Skeptics for 14 years, with no apology, because I likened LRL detection to that of a Magnetometer, and stated that if you increased the sensitivity of a Magnetometer 300 times you would detect the Fields of non-ferrous anomalies.

Estaban, you are a wise man, gracious enough to cater to the demands of unappreciative, dis-respectful fools. I respect the value of your knowledge you so freely share. Thank You! Dell

[Esteban]

Dell, thanks very much.

Max, respect why iron targets aren't undetectable (sometimes yes!) is in relation with quantity of wire you use in coil. My general norm is few wire for non ferrous and much wire for ferrous + magnetic core. But OK, I use magnetic core (with very few wire) also here, but aluminium loop is very low impedance and closed gain more, this is the primary. Secondary is small ferrite core. Also great advantage is this: through the time iron targets degenerate in oxide and don't create the enough electric field, but good conductive target mantain this field as a charged battery. Remember, here also there are some chemist process between soil and targets.

I don't hear directly in speaker or phones, variation of voltage I convert in audible rapid and short tone.

[Seden]

Phew! Thanks Dell!

Dell,

No harm done, I was just surprised that's all.
JP, my multi-sensor project is down on the priority list right now. As usual too darn many irons in the fire (I must have adult ADD or something). Too be honest when I'm on my days off I go out placer mining and prospecting. Just bought my 3rd Mercury Sniffer off ebay (Johnson-Williams/Bacharach S-1) as the other 2 need work (bought the previous 2 for ~$70 each and one of them is a Jerome 411 that just needs filters and the Bacharach MV2 that drifts).
What I'm going to work on now is make up stakes with wires for the Associated Research "Vibroground" 4 terminal resistivity meter and start practicing. I'm into this Ancient River location that has multiple Ancient River formations from the different epochs and time to get really serious about using Geophysics to track down the best spots within these deposits. I also have a TDS meter so were into Geochemical aspect and for detecting the black sand I just use my White's MXT which over the years has proven effective time after time.

Did I mention I'm working on my vertical for 160+1750 meters? Sometimes I wish I was wealthy and could retire early so I can knock these projects off more quickly and still have time for my family. I'll be ordering a development type 8051 board that goes with the book this guy wrote so I can have a 2nd try at learning to program (got sidetracked after getting half way through when I attempted to take a Cisco class-BORING!). I love assembly so that will be something I can do at work with my managements blessing and will be for the multisensor detector.
Randy

[J_Player]

.

[J_Player]

Sometimes I wish I was wealthy and could retire early so I can knock these projects off more quickly and still have time for my family.

You mean you still have time for family and they haven't kicked you out yet? No wonder you are short of time for your projects!

I can see where you're going with your multi-detector concept. I may be going that route on a project I have been tinkering with after I get the analog version details worked out. It would simplify some critical timing setpoints in the transistor circuitry by replacing the signal circuits with more stable digital timing. But I have the same problem with time for the learning curve before I can actually apply DSP.

Maybe you can get Dell to help you go straight to the placer deposits instead of spending so much time building instruments to map the ancient river beds first. Last time I heard, all it took was a few photos of the site to locate the treasure with a pendulum.

Be sure to post photos of your first handful of nuggets when you make your strike.

Best wishes,
J_P

[Morgan]

BFO-LRL

You will not post the schematic and instructions for Clondike Clad? Maybe it is not good for us, but Clondike Clad wants to see it. It only takes a few minutes to make the post, and then Clondike Clad will have what he asked for. Why don't you want him to build the many meters aluminum can and power source detector?

Best wishes,
J_P

Hello
Yes,i will put schematic as soon as possible ,for him.
As you can see,i build this device long time ago,its very easy to build ,but i said to Detectoman Gold coin 50 m distance,it was a joke
This device is more usefull as +&- ion locator than treasure hunting...Its some kind of zahory+BFO.

Regards

[J_Player]

Yes,i will put schematic as soon as possible ,for him....
...i said to Detectoman Gold coin 50 m distance,it was a joke
This device is more usefull as +&- ion locator than treasure hunting...Its some kind of zahory+BFO.

Hi Morgan,
Zahori + BFO is a good if it finds aluminum cans from long distance farther than a metal detector. This is why Clondike Clad wants to build it. It can be used for long range farther than a metal detector will work. If he builds it, then maybe he will discover a method to make it discriminate gold. If he can do this, then maybe you will be happy he made the circuit, and maybe he will post the circuit for gold classifier.

Thank you for helping with your LRL circuit.
Best wishes,
J_P

[Clondike Clad]

All this information

BUT NO WORKING CIRCUITS ON THIS FORUM????????????????????????????????????...NOT ONE WORKING CIRCUIT.
HOW DO A GUY LEARN IF NO ONE WON'T HELP HIM.
......................ALL I WANT TO SEE IS A SIMPLE WORKING LRL CIRCUIT TO PICK UP A COIN AT 2 METERS NOT 30 METERS OR EVEN A MILE AWAY.
...........................JUST A SIMPLE CIRCUIT FOR 2 METERS ON A COIN.....

[Esteban]

BUT NO WORKING CIRCUITS ON THIS FORUM????????????????????????????????????...NOT ONE WORKING CIRCUIT.
HOW DO A GUY LEARN IF NO ONE WON'T HELP HIM.
......................ALL I WANT TO SEE IS A SIMPLE WORKING LRL CIRCUIT TO PICK UP A COIN AT 2 METERS NOT 30 METERS OR EVEN A MILE AWAY.
...........................JUST A SIMPLE CIRCUIT FOR 2 METERS ON A COIN.....

In advance... in advance... relax...

[Morgan]

LRL who works

BUT NO WORKING CIRCUITS ON THIS FORUM????????????????????????????????????...NOT ONE WORKING CIRCUIT.
HOW DO A GUY LEARN IF NO ONE WON'T HELP HIM.
......................ALL I WANT TO SEE IS A SIMPLE WORKING LRL CIRCUIT TO PICK UP A COIN AT 2 METERS NOT 30 METERS OR EVEN A MILE AWAY.
...........................JUST A SIMPLE CIRCUIT FOR 2 METERS ON A COIN.....

Hi
The Pistoldetektor circuit works.
Only need to find coil and ferrite solution

regards