why not a larger SEF coil?

[greasecarguy]

The 10 x 12 sef isn't that much larger than the stock SE coil, so why wouldn't one use a larger one to go deeper? Because of trash? Why not the 18 x 15 butterfly coil?

Interesting that only 2 additional inches would give so much more depth as Andy's article states.

 

[dewcon4414]

Some times a larger coil just wont be the best solution. You may be getting depth but your processor now has to dig thru more information... minerals, EMI, salt, more targets, and iron. The deeper you go the more difficult it is for the TID to be anywhere close to accurate. Also as your coil gets larger you loose sensitivity to targets such as gold and even coins. I think you will find in highly mineralized soil there comes a time when you just cant process the information and you just wont get any deeper no matter the coil size.

Dew

 

[UncleTom]

You end up with many targets under your coil at the same time in trashy areas. Open areas larger coils work great!

 

[NiagracountyNY]

I use the 18x15 S.E.F.I use it alot in parks and private land too if there isnt much EMI in the area.The coil works well in trash ,but you need to have a good ear to seperate sometimes.Pinpointing can be a problem sometimes also.The areas that have alot of power lines seem to give me trouble sometimes.i end up having to run sens low.I have dug my deepest coins with this coil.The deep coins were in areas i have gone over with the pro coil before.The coil is abit on the heavy side after swinging it for a few hours.I have some vids on youtube with me using it and recovering some nice finds .My handle on youtube is NiagracountyNY if you wanna check them out .I Highly recommend this coil,BUT it will not work great in all areas.If you are like me you will have a few coils ,each work well under certain conditions.Good luck,happy hunting.