Is it possible to increase the depth of this Detector

[Hammerhead]

Hello to everyone we have in Egypt is prohibited Metal Detector I found in the scrap market on this Detector which works well Is it possible to increase the depth of this Detector help Please

[Hammerhead]

[Skippy]

Does it work OK at the moment? It appears to have signs of water damage / corrosion, so I would suggest cleaning the circuit-board first.
Once you know it works, I would try re-shaping the search-coil to a round shape ( or square shape, if that helps fitting it into a box ). If you can work out how the coil is wound, you could also make your own larger ( or smaller ) one. It may be centre-tapped, as it has three connections.

[Funfinder]

Super, this is a fantastic find already, my congratulations!

But Hammerhead, maybe I really have to visit you and bring you some nice little pseudo-legal present
sometimes or even this year already - don't know. By ship from Cyprus, Greece or Turkey.

But for the moment of course you can make it deeper!
First you need a very stable coil-housing.

The most simple way is to use the coil you have already and make it double as wide with half of the windings.
But you should built the coil- and electronic housing very stable so the coil wires fit tight together!

And next you can add some variable resistor at the right solder-locations to increase sensitivity
or for high critical manual adjusting. But first we need to find out where these spots are.
You can do this by trial and error but the risk is high that you cause some shortcut if you do it wrong.

What works is to set a 10k variable resistor (potentiometer) to its max (10k) and reduce it to 1k
by turning it while holding the both cables to some pins who might be effective enough.
You should hear then if the detectors audio output changes somehow.

But perhaps we can find some schematics of this detector and locate the needed soldering-spots directly.

[Skippy]

Here is the user manual for the Super Scanner:
http://regton.com/instructions/secur...perscanner.pdf

If you plan on modifying this, I recommend doing some distance tests with common items, before you start. Example: coins of your country, some jewellery, and larger items like an aluminium drinks can. Then you will be able to tell what improvements / or not you have achieved.

[Funfinder]

Thanks for the info, Skippy.

At page 15 is written that its a motion circuit.

I have a similar hand-held-security-detector with motion circuit
and this one works already with doubled or halved coil.

And next the Garrett has some "Interference Elimination Button"
which seems to adjust the threshold level and / or sensitivity.
With some luck it will adjusts automatically to the larger coil.

[Hammerhead]

Does it work OK at the moment? It appears to have signs of water damage / corrosion, so I would suggest cleaning the circuit-board first.
Once you know it works, I would try re-shaping the search-coil to a round shape ( or square shape, if that helps fitting it into a box ). If you can work out how the coil is wound, you could also make your own larger ( or smaller ) one. It may be centre-tapped, as it has three connections.

Hello skippy very good diagnosis actually, I found her in the scrap market and it was raining heavily Detector broken Thank you for the feedback

[Hammerhead]

Thanks for the info, Skippy.

At page 15 is written that its a motion circuit.

I have a similar hand-held-security-detector with motion circuit
and this one works already with doubled or halved coil.

And next the Garrett has some "Interference Elimination Button"
which seems to adjust the threshold level and / or sensitivity.
With some luck it will adjusts automatically to the larger coil.

Mr. funfinder hello how are you my friend I'm sorry I do not understand anything that Google says very bad translation
I tried to increase the depth increased by variable Blue Now, too, I'm trying to amendment coil please Is it possible to explain to me by images Number of turns wire coil wrapped wire 2.5

[Skippy]

I cannot see any unusual components in it, so that helps when trying to modify / understand the operation of it. There's a 78L05 5 volt regulator, so that's one basic thing to check when fault-finding. The 4066 chip is probably used as a synchronous detector, turning the AC signal into a DC one. The DC signal is then processed by amplifiers, filters to perform the 'motion discrimination', there's several op-amp chips, including an LM324 type quad one.

[Funfinder]

Mr. funfinder hello how are you my friend I'm sorry I do not understand anything that Google says very bad translation
I tried to increase the depth increased by variable Blue Now, too, I'm trying to amendment coil please Is it possible to explain to me by images Number of turns wire coil wrapped wire [ATTACH]39036[/ATTACH][ATTACH]39037[/ATTACH] 2.5

Hi Hammerhead, everything is ok, I hope you are fine and will have a successful start for the new treasure-hunting-year!

But I am confused:
Is the Garrett now working or not? Because first you have written: "this Detector which works well"

If not, maybe the part shown on this picture is burned:



QX2 - should be some MOSFET (field effect transistor which regulates the incoming voltage)

If this is the culprit it would be pretty complicated to replace it
but you may be able to "override" it with some 50 ohm resistor.

Concerning the coil please just try to increase the size with using the half amount of the windings.
You also can try to built some DD coil because those are 2 coils in one (the coil has 3 connections).
But both coils of that 2in1 coil should have the same size.
You also can try a totally new coil which has the double length of wire.

But of course the larger the coil is, the less sensitive it will be for small finds.
So as Skippy said its the best if you test before how sensitive is the detector
so the coil is useful for the objects you wanna find.

And here is an ultra simple to built metal detector which needs just one LM348 chip (op amp),
2x 1nF capacitors, 2 coils with shielding, a buzzer (flat piezo beeper) and a 9v battery.
With some luck you can get the capacitors and the LM348 inside from broken electronic devices.
The detector is all-metal and finds a 2 centimeter coin at 10 centimeter distance.




You can find it on this website:

http://www.talkingelectronics.com/pr...tectors-1.html

if you search for:
OP AMP METAL DETECTOR

[Hammerhead]

Hi Hammerhead, everything is ok, I hope you are fine and will have a successful start for the new treasure-hunting-year!

But I am confused:
Is the Garrett now working or not? Because first you have written: "this Detector which works well"

If not, maybe the part shown on this picture is burned:

[ATTACH]39077[/ATTACH]

QX2 - should be some MOSFET (field effect transistor which regulates the incoming voltage)

If this is the culprit it would be pretty complicated to replace it
but you may be able to "override" it with some 50 ohm resistor.

Concerning the coil please just try to increase the size with using the half amount of the windings.
You also can try to built some DD coil because those are 2 coils in one (the coil has 3 connections).
But both coils of that 2in1 coil should have the same size.
You also can try a totally new coil which has the double length of wire.

But of course the larger the coil is, the less sensitive it will be for small finds.
So as Skippy said its the best if you test before how sensitive is the detector
so the coil is useful for the objects you wanna find.

And here is an ultra simple to built metal detector which needs just one LM348 chip (op amp),
2x 1nF capacitors, 2 coils with shielding, a buzzer (flat piezo beeper) and a 9v battery.
With some luck you can get the capacitors and the LM348 inside from broken electronic devices.
The detector is all-metal and finds a 2 centimeter coin at 10 centimeter distance.


[ATTACH]39078[/ATTACH]

You can find it on this website:

http://www.talkingelectronics.com/pr...tectors-1.html

if you search for:
OP AMP METAL DETECTOR

Hello my friend Detector works very well But the depth is not good Yes my friend coil windings double the number 53 the size of about 15 cm
Do you suggest I increase coil size to 20 or 25 cm and underestimate the number of turns to 25 curlSecondly, this is the last hunt me in this winter Gold Old 68-year marriage and another 23 years Dblh

[Hammerhead]

See my friend I made this Russian detector and helped me great Greek our friend Arionas I'm taking your advice and I'm trying to be with me more than the detector And also we have a far Mirage circle bought from Mr. Seven of Canada

[Hammerhead]

See video experience Mirage and I want your comment http://www.geotech1.com/forums/showt...terested/page2

[Skippy]

The depth of your super scanner is small because the coil is small in one direction. If you re-shape the coil so it is circular, or "square with rounded corners", the inductance will change very little. Then, hopefully, it will still function correctly, and the depth may be doubled. Only then should you consider larger diameter coils. If you do make a larger coil, I recommend you do it scientifically, using mathematics to find the correct number of turns. There is a Javascript coil inductance calculator on this website, which can be used to work out a good solution.

Here:
http://www.geotech1.com/forums/showt...oil-Calculator

[Dave J.]

The searchcoil is not induction balance, and appears to be bifilar centertapped. So it's probably an eddy current dampened oscillator, a common operating principle for low cost low sensitivity metal detectors.

No matter what you do to it, it's never going to have the kind of sensitivity you'd expect from a medium performance VLF or pulse induction metal detector.