Delta pulse sniffer xr71

[Chamath]

Hello.

Can anyone with good experience tell me if this device works well. I only have the diagram below. Actually I designed it like that. But after connecting the coil to it, it doesn't work properly. After connecting the power supply, the sound comes from the speaker. It was gone in a few seconds. Here it shows 306hertz and I made and connected a coil of the following size to this device.

1) Is this not working because this diagram is wrong?
2) Or should the values given in some sections be changed?
3) In which way should the potentiometer be placed before giving the power supply to this?

I replaced irf740 with irf840 here

Please help me to solve this problem.

Thank You all.....

I have a schematic and I believe it is correct

[kt315]

DP is closed off matter for majority of the people. they all had bult and checked the detector. so noone does want answer you.
people get tired to see one schematic every time long time, by years.
your design is turkish. maybe you must ask in turkish forum.

[kt315]

this guy got 6 meters on a car. https://www.youtube.com/watch?v=JSEi1MEN-Vc
do this test. repeat.

[Chamath]

My device is working now. But a 30cm object with a 60cm coil only works about 2 feet away. Now I have a big problem with depth.what i do for that?

[kt315]

object
---
concentrate your mind. what it is? coin? plier? screw driver? meteorite 100 gram? hammer? gold 200 gram?

[Chamath]

I tested this kind of lid. It is a big lid about 30cm

[GeoMax]

This is made from stainless steel... Not a good test object.

[green]

This is made from stainless steel... Not a good test object.

Anyone know the time constant for a large stainless steel lid?

[Chamath]

How should I check this as you say? I just changed a few resistors as someone else told me on another web page. He said it made the device very sensitive to gold. I didn't believe it. He had a video showing how it works. It is an article with some old details. The owner could not be contacted in any way

I found that a 6cm gold ring at 50cm worked really well. He used a search coil of about 20cm.

In fact, in many places I have seen this device work at a good depth into the ground. I believe there is a value change to be made in other parts here. It is just my personal opinion

Can someone explain it? I think there are many people here who have designed this device well

[Chamath]

This is made from stainless steel... Not a good test object.

Why do you say this? This is not only made of stainless steel. When a magnet is attached to it, the magnet sticks to it

[kt315]

Can someone explain it? I think there are many people here who have designed this device well

you must read the theory, ar First. begin from those articles

Geotech - Metal Detectors - Projects (geotech1.com)

Pulse Induction Detectors

Corbyn PI (J.A. Corbyn, Wireless World)

EE Treasure Hunter (Mark Stuart, Everyday Electronics)

Gary's Pulse Induction Metal Detector (from Gary's Chemelec web site)

GoldPic PI (Trevor Hill)

Hammerhead Carl Moreland

Microcontroller PI Treasure Hunter (Mark Stuart, EPE)

Proscan PI (ProScan)

Pulsdetektor This is a German web site that has several PI projects, and a discussion forum. No English, but the schematics are easy to figure out.

Sandbanks PI (P.J. Wales, Practical Wireless)

Twin Loop Treasure Seeker (Robert & David Crone, ETI)

[GeoMax]

Hi Chamath,
stainless steel is magnetic... yes for sure but not very good. Better, use an ordinary hammer. This one is guarantee made from iron.

@How a detector works....
Read the suggested articles by kt315's first. Than you will slowly understand why a changing of resistor values does it not make a good detector for gold. I also can highly recommend to read the book Inside the METAL DETECTOR - Second Edition. This book is also good for teaching the basics you want to know. Alternatively, you can check out this forum. There you can also find every answer to your questions. Geotech forum is a good knowledge base.

[Chamath]

Hi Chamath,
stainless steel is magnetic... yes for sure but not very good. Better, use an ordinary hammer. This one is guarantee made from iron.

@How a detector works....
Read the suggested articles by kt315's first. Than you will slowly understand why a changing of resistor values does it not make a good detector for gold. I also can highly recommend to read the book Inside the METAL DETECTOR - Second Edition. This book is also good for teaching the basics you want to know. Alternatively, you can check out this forum. There you can also find every answer to your questions. Geotech forum is a good knowledge base.

Are you saying that this device has not useble for gold?

[Qiaozhi]

Are you saying that this device has not useble for gold?

Pulse induction detectors can be designed to detect either low conductivity or high conductivity targets. Unless the detector has controls to adjust the TX pulse rate, TX pulse width, sample pulse width and sample delay, then it is usually designed for one or the other, but not both together.
The Delta Pulse is generally used to detect large high conductivity targets. For small targets, such as gold nuggets, you will need something else.
The other use for PI detectors is on the beach, and these types will have sample rates set to ignore salt water.
If you want something to detect small gold, then it must also have a ground balance setting.

[Chamath]

Pulse induction detectors can be designed to detect either low conductivity or high conductivity targets. Unless the detector has controls to adjust the TX pulse rate, TX pulse width, sample pulse width and sample delay, then it is usually designed for one or the other, but not both together.
The Delta Pulse is generally used to detect large high conductivity targets. For small targets, such as gold nuggets, you will need something else.
The other use for PI detectors is on the beach, and these types will have sample rates set to ignore salt water.
If you want something to detect small gold, then it must also have a ground balance setting.

I don't need to dig for little gold with this. 25kg - 40kg only need to search for large quantities