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Metal Detectors Surrounding Noise
sweetsummer1  
Posted : Tuesday, 14 April 2015 12:29:23 AM(UTC)
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Hello all,
Hope you are keeping warm. It is pretty cold atm

I am new to metal detectors and got two questions:

1) Do metal detectors sense surrounding metal ? Say if I attach it to a car, would it sense the car? or do metal detectors have projected sensing?

2) Has anyone tried connecting a search coil to a microcontroller (Arduino for example?)? I wanted to make my own detector but thought that using a proper coil would reduce false readings.

cheers
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creamer  
Posted : Tuesday, 14 April 2015 8:50:51 AM(UTC)
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There was a show on the tele called Meteorite men and they were towing a very large coil some ways behind a quad bike. As for a car i would say that there would be heaps of interferance if the coil was anywhere near it. Sounds like you on a mission.

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sweetsummer1  
Posted : Tuesday, 14 April 2015 12:15:16 PM(UTC)
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Hi Creamer,

Thanks for your reply. Yea, I think it will be pretty challenging to attach one to car.
Do you think even highly shielded coils won't work?

cheers
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Mudwiggle  
Posted : Tuesday, 14 April 2015 1:08:35 PM(UTC)
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As far as I am aware, the only thing you could shield with, is distance. The proximity of the car will mask everything. I would think you'd need to look at a metre separation as a minimum. Then there's a real chance of electrical interference from the ignition, unless it's a diesel.
You'd have to be driving very slowly (around 3km/h) to hit anything other than a big target.

Can I ask the application?
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sweetsummer1  
Posted : Tuesday, 14 April 2015 1:20:06 PM(UTC)
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Hi Mudwiggle,

I am trying to scan a newly purchased land for buried utilities (i.e. manhole covers).
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Erickd  
Posted : Tuesday, 14 April 2015 2:03:05 PM(UTC)
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I would have thought a good detector set on All metal mode / stat setting ( non-motion) would get down deep and able to trace pipes as you walk
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Mudwiggle  
Posted : Tuesday, 14 April 2015 2:10:59 PM(UTC)
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Personally, I'd phone the local council for a copy of their utility network survey... Lot less effort
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kiwisouth  
Posted : Wednesday, 15 April 2015 10:06:41 PM(UTC)
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Agree with you there Muddy. Council will have something
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sweetsummer1  
Posted : Thursday, 16 April 2015 1:04:07 AM(UTC)
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Thanks Muddy and Kiwisouth. I have contacted the council and hopefully they will get back to me sometime next week.

Just a general question though, I actually thought metal detectors only sense what's below them (projected sensing), is that wrong?
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Metal Kiwi  
Posted : Thursday, 16 April 2015 8:58:06 AM(UTC)
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Originally Posted by: sweetsummer1 Go to Quoted Post
Thanks Muddy and Kiwisouth. I have contacted the council and hopefully they will get back to me sometime next week.

Just a general question though, I actually thought metal detectors only sense what's below them (projected sensing), is that wrong?


The Minelab detectors I use have DD coils and I have found that there is some radial sensing. I think it is mainly from the mid point of the coil front and rear where the two windings meet.

MK
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