Walk Through Metal detector Circuit digaram

[jamil_tech]

Hi,

Yes In my circuit both coil winding with same. in lower sensivity the circuit is ok, but if I increse sensivty a little circuit is unstable. What the good other relacement for FET transistor BFW11 ?

Is there any way I use Oscilascope here for fine tune the circuit ?

Regarding Gold PIC microconterller PI there is no Code for microcontroller. I already start making grys PI PCB , hpefully very soon i will make it. But I need Idea about its coil , how can I use it as walk through.

What do you think about T/R Locator Metal detector ( http://sevzirfo.narod.ru/trlocatorver1.gif ) , and which two box circuit is best for me in your own experiance.

Could I use T/R Locator metal detector as following form, both coil will be paralal or perpandiculer ?


Thanks

[Carl-NC]

This is how most walk-throughs are designed... multiple TX coils on one side, and multiple RX coils on the other. They create detection zones.

I own a Garrett walk-through, always intended to take it apart and show how the coils are set up, but never have. It's that round tuit thingy...

- Carl

[Pareto]

Walkthrough metal detector is very interesting. I am very much interested about this. But I never found any link in internet and no other forum ever discuss it before as much here i found . Carl we want more .

Thanks

[jamil_tech]

This is a picture of a multi zone coil inside walk through. It is may be TX RX system. But its circuit is too complex That I cannot understand. I need help plz.

[jamil_tech]

my messanger and email address

Hi
My email and messanger address is : [email protected] , [email protected]

[Qiaozhi]

Regarding Gold PIC microconterller PI there is no Code for microcontroller.

According to the Gold PIC website: The semi-kit contains a bare, fibre-glass, tinned, single-sided printed circuit board, the pre-programmed microcontroller integrated circuit containing the embedded software, printed assembly instructions and the circuit schematic. The microcontroller is 'code-locked' to prevent duplication of the firmware.
In other words you need to purchase the pre-programmed microcontroller. Once you have the working microcontroller (and you can see how it works) it should be possible to create your own source code to do the same thing.

I already start making grys PI PCB , hpefully very soon i will make it. But I need Idea about its coil , how can I use it as walk through.

See last reply in this post.

What do you think about T/R Locator Metal detector ( http://sevzirfo.narod.ru/trlocatorver1.gif ) , and which two box circuit is best for me in your own experiance.

I don't think a 2-box would be good for this application. These detectors are designed to detect large cache sized targets.

Could I use T/R Locator metal detector as following form, both coil will be paralal or perpandiculer ?

According to Carl, this is the usual coil configuration, and in the images you posted it looks like they are parallel, so I suspect this would only work well for a P.I. circuit.

[Qiaozhi]

Here's a neat explanation of how a walk-through detector works (with animation) -> http://travel.howstuffworks.com/airport-security3.htm

Depending on the complexity you require for your project, multi-zone coils may not be required. Just have a big loop on one side of the arch connected to your P.I. circuit.

[jamil_tech]

HI Qiaozhi



Thanks for your lots help. Please tell me finally which PI other then gold scan ( coz it will complex my project for searching coding ) you personally tested and found best performance, if possible please send me revised schematic ( coz my previous experience most of schematic have some problem only expert people can solve this) with PCB layout and parts list. I like to test one, which you tested already.


I am sorry for troubling you so much. You may thing me a lazy student, but believe me I already made half dozens circuits and no one is satisfactory label.



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[Qiaozhi]

HI Qiaozhi



Thanks for your lots help. Please tell me finally which PI other then gold scan ( coz it will complex my project for searching coding ) you personally tested and found best performance, if possible please send me revised schematic ( coz my previous experience most of schematic have some problem only expert people can solve this) with PCB layout and parts list. I like to test one, which you tested already.


I am sorry for troubling you so much. You may thing me a lazy student, but believe me I already made half dozens circuits and no one is satisfactory label.



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Hi Jamil,

Many people here have successfully built the Hammerhead. It was designed by Carl as a project to learn how P.I. detectors work, and to allow you to experiment. I have not built this myself yet (maybe one day) but this is a known good design. Also, if you get stuck, there's a special Forum under Projects for the Hammerhead where you can get advice.

Another one that might be worth looking at is the Sandbanks P.I. -> http://geotech.thunting.com/cgi-bin/...anks/index.dat

Personally I would go with the Hammerhead.

[jamil_tech]

What do you think about Delta Pulse and SNIFFER XR-71 ?

[jamil_tech]

Hi,

I need a information, I found most of the big coil metal detector use PPPEAR or MPEAR capacitor, which is rare in electronic shop. Can I use myler or ordinaray capacitor instead of this capacitor.

What is the good replacement of transistor BFW11 ?


Thanks
Jamil

[Qiaozhi]

Hi,

I need a information, I found most of the big coil metal detector use PPPEAR or MPEAR capacitor, which is rare in electronic shop. Can I use myler or ordinaray capacitor instead of this capacitor.

What is the good replacement of transistor BFW11 ?


Thanks
Jamil

Is this capacitor for an I.B. or P.I. design?

I checked in a transistor guide and there are two possible substitutes for the BFW11 -> BFW16A or 2N4416.

[jamil_tech]

what kind of metal detector of my design

First i need to know what kind of metal detector of my design ( Schematic I post already ) . Is it IB or frequency shift type?

and is there any same kind of circuit you see before? if yes plz give me link.



thanks

[Qiaozhi]

First i need to know what kind of metal detector of my design ( Schematic I post already ) . Is it IB or frequency shift type?

and is there any same kind of circuit you see before? if yes plz give me link.



thanks

Do you have a better schematic than this one?
There are several component values missing and no pin numbers on the ICs.

At first sight it looks like an I.B., especially since there is a tuning capacitor across the TX coil, but this is an unusual design and really needs to be redrawn in order to get a better understanding of its operation.

[Unregistered]

this walk-through metal detector is a very interesting topic in this forum. But unfortunately very little information in web . If anybody have more information regarding walk-through please share it here in this forum. I am a new learner but i am very much interested about walk-through circuits. I am sure there is a big difference between walk-through and coin hunter metal detector. So it is not a very good idea just make a walk-through metal detector from a coin detector.