this segment is what coil and why and it should give you a bit of an idea on how to decide which
coil to use and in what circumstances firstly with a big coil like a 25 inch round from nugget binder
we find that these coils are much better if we're wanting to get some extra depth if we want to
cover a bit more ground and typically they need to be used in areas where there is less ground cover
now look with those bigger coils like i said you need to have areas that don't have as much
ground cover but you're going to get much better depth using one of those when you're targeting
large objects so i'm talking pieces of gold or big objects things like half a house brick or
a 40 ounce nugget that's where your big coils come into their own in getting you that extra depth
unfortunately when you're using a big coil there is a bit of a trade-off in that you will lose some
sensitivity to the smaller gold so big gold open area want to cover a lot of ground quickly the big
coil is the way to go conversely a small coil like our gold monster five inch coil is very very good
for smaller pieces of gold close to the surface it has extra sensitivity in it that will mean it can
get targets that some of the larger coils can't there's not always one coil to cover the whole job
but in using a small coil i can use it in areas where there's a lot more ground cover so i can
move in around the bits and pieces and still get the coil close to the ground i can also use it
where i've had a patch and i've got most of the gold off with my bigger coils but i want to go
back in and clean up all the little specks that are left so in that case i'm going to use my small
round coil or a small elliptical coil as well as having solid and spoke coils if you've seen in the
last two that i had there's also an elliptical shaped coil that we have here now an elliptical
shaped coil will make it a little bit easier to pin point it's a mid-range size so it's good as an
all-round cork with a great balance between depth on bigger stuff and sensitivity on small gold
so with the different sizes that should give you some indication on which coil you should select
when you're out there working in the field as well as size on the coil mattering because certain
coils are better for certain objects and certain depths there's also the importance of the windings
in the coil so a winding in a coil is the way that the wire is configured to allow us to get
different results for example a double d coil that has two windings that are shaped like a double d
or two d's back to back you'll see that up on the screen there now that kind of coil is very
very good if i'm working in the highly mineralized ground and i want to knock out some of the effect
of the ground mineralisation if i'm working in an area where the ground is extremely saturated or
damp this will help reduce some of the noise that you get from the ground mineralization and if i
want to use some of the features on the minelab machines such as cancel mode a double d coil is
required now although a double d coil provides us a bit more stability in the mineralized ground
it's not usually my coil of preference my coil of preference on most of the later minelab machines
is a mono coil and as you'll see behind me there this mono coil has the windings or wire going
around the outside rim of the coil what this does is change the signal it comes out so that when it
comes down the signal looks like it's coming out in an ice cream cone shape with this type of coil
i get better sensitivity to the smaller gold i can punch deeper than what i can with a double d coil
however i may find that some ground conditions are too mineralized for me be able to get a
stable operating environment and that's when i look to going back to the double d coil
there is one other type of coil that i used to be around and used quite a bit
it was called an ai or anti-interference coil the windings on this coil were actually in a figure
eight and what this was able to do was to make it extremely stable in the highly mineralized
ground in areas of massive amounts of electrical interference or on some of the salt lakes it's
similar to how cancel mode works on some of the mine lab machines but you do tend to lose a little
bit of depth and these coils have probably been used a bit say behind an old quad bike drazer
drag coil because we're able to knock out the interference from the alternator on the quad bike
but we don't see as many of them around now as the mylab technology has continued to improve to knock
out the effects of emi now whilst double d coils have become less used or less frequently used
whilst prospecting for gold double d coils are still very very important when i'm looking for
coins and relics a double d coil on a coin and relic machine gives me the ability to be able to
have maximum discrimination as we know anywhere where people have dropped goodies like coins
relics and jewelry they've also dropped a lot of trash so if you've got a coin and relic machine
make sure you look at your double d coils because they are much much better in that environment than
in most of the gold fields areas that's giving you a bit of an overview on some of the more commonly
known coils there are some windings on some other coils that are used for specific purposes but in
general the information you have there should put you on the right track to selecting the right coil
and the right windings configuration for your next prospecting or treasure hunting adventure