help me - help me

[J_Player]

Hi j_player,I did not say is false schematic! I have this schematic in this video and just did the rear of coil NMR fenomeno!And I know that works very well (SCHEMATIC) why I did this. have a good day>zarkinos

Hi sakis,

Maybe I do not understand your words.
Maybe you meant to say that you can confirm this circuit is not fake.
This is the kind of report that I am interested to read about.

It seems like your version is changed to include your NMR modification.
Can you tell us about this NMR part?


Best wishes,
J_P

[WM6]

But he did not need to wait for the proper atmospheric conditions.
He was detecting on any day even if it is raining.

Did it suit well to all continents?

[J_Player]

Did it suit well to all continents?

Hi WM6,
He only reported from the European area.
But this metal locator was originally sold in the USA by the thousands.
So I know from all the treasure recovery reports that it is working in the USA.
And I remember a report from Belgium and from South America that it was working in those places too.

Actually, I have not had a reason to even think about this locator for a long time until now when kahyal says help me- help me , i need a pistol detector project -schematic
Then, I soon learned that he would accept only a a pd that detectors metals --- not an electrostatic detector.
This is the only full schematic of a PD which detectors metals that I could think of.
So I try to remember from old forum posts that are no longer online.

It is good that I saved the circuit diagram.
I have had to correct this schematic several times to make it accurate for the original design.
There are several similar circuits which are modifications of this original factory design.
But I believe I have arrived at the original design using the original parts, or a close substitute part that will perform the same.


Best wishes,
J_P

[sakis1]

Hi sakis,

Maybe I do not understand your words.
Maybe you meant to say that you can confirm this circuit is not fake.
This is the kind of report that I am interested to read about.

It seems like your version is changed to include your NMR modification.
Can you tell us about this NMR part?


Best wishes,
J_P

Exactly this

[COLOR="rgb(65, 105, 225)"]does not change anything, as much for the nmr is the functionality in MRI[/COLOR]

look at google images for NMR

Sorry for the English language but I have forgotten somewhere!!!!!!!!!!

[WM6]

It is good that I saved the circuit diagram.
I have had to correct this schematic several times to make it accurate for the original design.
There are several similar circuits which are modifications of this original factory design.
But I believe I have arrived at the original design using the original parts, or a close substitute part that will perform the same.


Best wishes,
J_P

You done great work, thank you J_P.

[aft_72005]

I will try to find some of the original operating instructions for this locator.


J_Player , Thank you for good comments ,circuit was interest me .
I will continue study this thread and wait for study more .
Best regards.

[ma330]

Schematic is very good and practical Excellent j-p.Congratulations
I pcb design.Everyone wants to pcb To send him an email
Sincerely

[usta]

Schematic is very good and practical Excellent j-p.Congratulations
I pcb design.Everyone wants to pcb To send him an email
Sincerely

so why you don't want to upload here?
"" Jack or mesy64 or meysam!!, I read you PM, i sent a PM to you too, if you want, you can read it!""
regards

[ma330]

so why you don't want to upload here?
"" Jack or mesy64 or meysam!!, I read you PM, i sent a PM to you too, if you want, you can read it!""
regards

I believe you have a problem that does not work from the Society of Friends
You can share this problem with the forum administrator or moderator of the forum to ask for a better IP block MESY64 OR JACK OR MEYSAM or wm6 or jeo and.....
because I do not want to kill those who do not bother to exchange useful information for people who have come down to personal problems

[WM6]

regret.....projects that are without pcb they are only a idea
best regards

Here you are:

Coil housing PCB (4.8"x3.6"):

[WM6]

Main (pistol) housing PCB (4.8"x3.5"):

[J_Player]

Main (pistol) housing PCB (4.8"x3.5"):

Wow..

Cool WM6
Now the the Persian factory can begin commercial production.
But we will not need to pay thousands of euros for a Persian copy of this metal locator, because we have the complete design here that we can build for maybe 20-25 euros.

Excellent work.
Did you check for errors?
So far, I can see that VR1 (50K) and VR2 (100K) should not be put on the PCB.
This should be a full size 50K control pot that is mounted on the box where it is accessible for the treasure hunter to make adjustments in the field when needed.
If you added these as a board-set pot and a trimmer for the sensitivity, then they are a modification to the original design.
But maybe I have the wrong idea.
Can you tell why we see them on the board?


One note: Some of the old mica capacitors are maybe too large to fit on this board easily.
The only mica capacitors are one for the TX coil and one for the RX coil.
These two mica capacitors can be soldered directly to the coil wires if you want.
The reason for using mica is because they have very good temperature stability, and will not drift so much like other capacitors when the temperature changes.
If the capacitors at the coils drift too much, then you can lose the good performance for detecting tiny signals.


Best wishes,
J_P

[Fred]

WM6, with all respect, this is a very ugly design

[J_Player]

Initial tuning instructions:

I have found only parts of the instruction manual.
Since it is copyrighted, I can not publish it here.
But I can paraphrase what it says.
The words I use are different, but the meaning is the same as what they say in the factory instructions.
After you read the factory instructions you will find my instructions below them.

Factory instructions for initial calibration:
The meter is much more sensitive than the sound circuit. So all calibration is done by watching the meter.

First set the sensitivity and the null adjustments.
Move the locator away from all metal things, then turn the null control to the center of its adjustment.
Turn on the power switch. You may or may not hear a sound from the speaker when you turn on the power.
If you do not hear a tone, then turn the sensitivity control down until the meter moves to the 6 position.
If you do hear a tone when you turn on the power, then adjust the sensitivity either up or down until the meter moves to the 6 postition.
Slowly turn the null control until you find a minimum meter reading. This is the best null adjustment.

Another way to find the best null adjustment is to turn the sensitivity control down the meter reaches the 6 position.
Then turn the null control until you see a minimum meter level.
When turning the null control only increases the meter level, then you have found the best null.
Turn the sensitivity so the meter reads half way between 0 and 2. Then shut off the power.

Check to see if the locator will operate to pinpoint correctly.
Put a USA dime on the ground where there is no metal near.
Then turn on the power and pass the search coil Slowly over the dime at a height of 2 inches (5cm) above the ground.
You should see the meter readings below in the diagram when the search coil is passed at different locations above the USA dime coin.



My note about the meter:
At this time, we still do not know what kind of meter is used in this circuit.
This meter is connected in a manner that appears to be measuring a current that will reach a maximum of 1ma when the meter is moved all the way to the right for full-scale movement.
We will not know if this is correct or not until someone makes some tests and reports back to tell what is the correct value.
I am presuming the meter is a 1ma full scale meter, but not sure.

My other note -- if you do not have a USA dime:
USA Dime is 90% copper with some nickel alloy added for the top and bottom to give the silver color.
You can cut a copper disk to the same size as a USA dime to find similar results.
USA dime dimensions: 17.91 mm diameter 1.35 mm thickness 2.268 gm weight.

This is the end of the initial factory calibration instructions.
Now you can read my instructions for the home-built pistol version of this metal locator:


My instructions for PD adaptation of this locator:
The instructions below are my instructions which were not given by the factory.
These instructions are important because they are special instructions for when you are making this locator using all your own parts for a pistol design.
The original factory version of this locator was not a pistol design.
The original factory version was a rifle design, so they did not include pistol instructions.

Final checks before making PD calibration:
To begin, let us assume you have completed the construction of the PD version of this locator.
Before you put in the battery, you should make these checks:
First look at the circuit board or the breadboard closely to make sure you have good solder joints.
Also check to see there is no place where the solder is spread out where it is touching a different conductor that it should not touch.
Then clean all of the solder joints and the circuit board with alcohol and wipe it dry with a soft cloth to remove any flux residue.
Methylated spirits is the best solvent to use.
Look at the wires that connect the coils to the circuit.
These wires should not be long wires tangled through the box.
They should be kept short so they do not pick up electronic noise from the rest of the circuits.
Then adjust the sensitivity control to the minimum (0% sensitivity), and put the null control to the center of the adjustment range. (50% at half of the null).
Finally, put in the battery and turn on the power.
Be ready to turn it off if you smell smoke or you see any other electrical problem like the meter stuck to full reading.
If you have no short circuits and everything is connected as it should be, you may hear some sound from the speaker, or maybe not.
Speaker sound is ok, and no sound is ok too.

At this point you will need to adjust the position of the RX coil for a null on the search coil.
First, to explain about the null:
The RX coil is designed to detect anomalies in the VLF wave transmissions that it receives.
But it is located nearly touching the transmitter coil that is broadcasting strong VLF waves which will interfere with the detection that the RX coil is trying to find.
This is the reason why the RX coil is positioned to cross over the center of the transmitter coil.
At this position there is very little of the TX coil power interfering with the RX coil detection.
But we must adjust the position of the RX coil exactly to find the minimum amount of interference from the TX coil.
When we find the position for the minimum interference, we call this the null position for the RX coil.
In this circuit design, we also see there is a null adjustment knob which the designer included to make very fine null adjustments electronically, after we find the best null location to put the RX coil.
The idea for nulling is to first put the RX coil in the best null position that we can find while the electronic adjustment is set to the center of its adjustment range.
Then, you will have a perfect null location with no interference from the TX coil.
This means that the RX coil will only detect anomalies that it finds in the air, not interference from the transmitter.
You will still be able to make fine adjustments when there are physical conditions that cause the null to drift so it is no longer perfectly nulled.
The control knob can make these fine adjustments.
You may need to use the null control knob to make adjustments when you are detecting near mineralized soil, or if some metal part inside your box is moved, or other similar conditions.
So you want to find the best null position for the coil while the null control knob is in the center position.
Now, a method to do this:

How to make the null adjustment:
First move your PD locator away from all metal things. Make sure you do not have rings, watches or other jewelry on your hands.
Leave the null adjustment potentiometer at the center position, and turn the sensitivity until you find a meter reading at the middle of the meter scale (50% meter).
Then move the RX coil until you find the lowest meter reading.
You can move this coil after you loosen the screws at the slotted hole.
Then slide the coil up or down to find where the meter reaches the lowest reading.
If the meter reading reduces down to 0, then turn up the control knob for more sensitivity until you see a meter reading on the scale.
Then make more adjustments to the position of the RX coil until you find the lowest reading.
You should find a position for the RX coil where it shows the lowest meter reading, and the meter will read higher if you move the RX coil up or down.
When you find this position for the RX coil, then you have found your best null position.
It may be necessary to turn the null control knob a little to find this location.
You can turn the knob anywhere between the 40% null to 60% null if it will help to find the lowest meter reading.
When you cannot find a lower meter reading from moving the RX coil and from turning the null control knob between 40% nd 60%, this means you have found the best null position for the RX null.
You can tighten the RX coil in this position so it will not move from the null position that you found.

Note:
This lowest meter reading position should be found when the electronic null control is in the center position between 40% and 60%.
If your null control knob must be set less than 40% or more than 60% to find the lowest meter reading, then you will need to move the coil farther.
Maybe you will need to make the slots longer so the RX coil will move farther.

Final check to see if you are done with the null adjustment:
When you are finished with the null adjustment, you should have found a location for the RX coil that gives the lowest meter reading when the Null control knob is in the center.
Any movement of the RX coil will cause the meter reading to increase.
Also, any adjustment of the null control knob will cause the meter reading to increase.
Look to see the RX coil is not pushed to the end of the slotted hole -- it can be moved farther in either direction, but if you move it up or down, the meter reading will increase.
Look to see the null control knob is set near the center (between 40% and 60%). When you turn it to the right or left, the meter reading will increase.
If all of these checks are correct, then you are finished with the null adjustment.
When you complete this null adjustment, you are ready to make the pinpoint test.

Extra tips for a good null:
These tips should be used in the early construction stages of the project...
Keep all the metal parts of your PD separated from the coils as far as possible.
The meter and battery and controls should be at the back, away from the coils.
The only parts that should be close to the coils is the transmitter and receiver part of the circuits.
If you use a 2-board design, you can put PCB-1 inside the coil housing or inside the PD box very close to the coils.
You want to keep the wires that connect from the coils to this board as short as possible so they do not pick up or send out unwanted electronic noise.
If you are building with a single board design, then keep the parts of the circuit for the TX and RX coil at one end of the board, near the coils.
And keep the power circuits for the speaker and meter at the other end of the board away from the coils.

Final pinpointing check:
The final check for the PD after you have a good null is the pinpointing check.
You can do this the same as the factory check.
Use the diagram below to check that you have the correct meter readings when you pass the search coil over a USA dime at different parts of the coil.


I will continue to search for factory instructions to see if I can find more tips to post.
Thank you to WM6 for his help with the circuit boards.
Maybe others will help also to make this a good project.
When more time has passed to add more details and to make corrections to any errors, I will compile a complete project for hobbyists to build.


Best wishes,
J_P

[mehdi]

it looke to be very good schematic!