Smaller Coil In Trash, why?

[DaugBiscuit]

I do not have a smaller coil (yet), but I keep hearing people say the smaller coils are good in trash. Can someone explain to me why a small coil works better in trash as opposed to the standard 11" DD coil? I mean, doesn't a signal go out and a signal comes back - what difference does a smaller coil make as far as the sounds coming back?

Can't you see my inexperience coming through with this question?

Don't laugh, I will apologize for the stupid question while I beg your indulgence but pleas try to help me understand..

Don

 

[john4840]

I do not have a smaller coil (yet), but I keep hearing people say the smaller coils are good in trash. Can someone explain to me why a small coil works better in trash as opposed to the standard 11" DD coil? I mean, doesn't a signal go out and a signal comes back - what difference does a smaller coil make as far as the sounds coming back?

Can't you see my inexperience coming through with this question?

Don't laugh, I will apologize for the stupid question while I beg your indulgence but pleas try to help me understand..

Don

The smaller coil helps you find coins and desirable targets in high trashy areas. The smaller coil give you better seperation of targets. Has nothing to do with the sound.

John

 

[Mtnmn]

A smaller coil because of its smaller size naturally scans a much smaller area than a large size coil. As a result there are far fewer targets under the smaller coil at any given moment in time, making it much easier for the detector with a smaller coil to separate a good target from in among just one or two other targets than it is for a detector with large coil trying to separate a good target from possibly as many as a half dozen other targets at any moment in time. This is an simplified answer to why smaller coils have better separation abilities than larger coils.

 

[DaugBiscuit]

A smaller coil because of its smaller size naturally scans a much smaller area than a large size coil. As a result there are far fewer targets under the smaller coil at any given moment in time, making it much easier for the detector with a smaller coil to separate a good target from in among just one or two other targets

Ah, now that makes sense, thanks for the reply. I am convinced that the smaller coil gives better separation because everyone says that, but I like to know how it is able to give better separation and your response makes sense.

If I may follow up with another question; lots of people also say the smaller coil will not go as deep as the larger coils. Is that a true statement or does that depend entirely on the particular coil?

Thanks for the reply,
Don

 

[Mtnmn]

It is generally a true statement, but type of coil design and its configuration will also affect overall coil depth. Detection depth is pretty much (but not entirely) in direct proportion to the size of the coil. For that reason a large coil will almost always have more depth than a smaller coil. Although on the XT-70 I have a 6" DD HF coil which will definitely hit deeper on nickels than its 9" MF concentric cousin will.

 

[Big Boys Hobbies]

Small coils allow you to separate targets better. With a smaller "footprint" the machine is int seeing as many targets at once. Makes it easier on machine to tell what is under coil and not blend several targets.

Any questions feel free to contact me.