Searchcoil designed for patch hunting. Mount to your own design. This coil is a specialty coil for those extremely large nuggets at depth. There are no searchcoil on the market today that is bigger than the Mother ship!
If this coil can't find that hidden Nugget Patch, no searchcoil will!
These coils were originally produced in the Anti-Interference (A.I.)
configuration for the SALT LAKES in Western Australia but have become a
great search tool for many areas around the world. We produce these
mainly in the A.I. configuration but also as the DD. We find that a mono
coil of this size is too big and will be very noisy. They have
excellent depth capabilities which is why they are such good patch
finders but their sensitivity to smaller targets, 1-2 grams and below,
is greatly reduced. For a 1-2 gram piece to be heard it would need to be
on the surface and the coil detecting speed quite slow. However,
finding the small pieces is not what this coil is designed for!
The 40 x 20 coils do take a little time to set-up and get
right in regards to towing / dragging but their performance is very
good once achieved. The main thing to remember is to protect the cable
from any snags or pulls from low lying bushes and rocks. Clear, flat
terrain is best. The coil can be around 1-2inches off the ground
depending on what you make the coil housing out of and remembering that
the coil needs to remain connected to the housing to prevent the bumps
of normal travel dislodging the unit. This can be achieved by cable ties
or nylon nuts and bolts. The coil housing is best made from timber as
is the arm which connects the unit to the quad bike. The skids for these
coils can be made from tough, durable plastic or conveyer belt
material. Just remember that some material can have wire re-enforcing
inside it so if you’re unsure, just wave the material to be used over
the detector coil first to see if it ‘sees’ the material.
If you are dragging this coil by quad bike we recommend
you use the A.I. coil and your speed to be about 5-7kms/hr which is
like walking pace or idle engaged with 1st gear and obviously picking a
relatively clear path. The Coil needs to be around 3 metres away from
the bike. This will provide quieter operation. If you are dragging the
coil behind a person then the DD coil will be OK and the same speed
applies, just be prepared for some hard work!
When setting this unit up on the skid you must ensure
this area is protected from anything which can pull or damage the cable.
By cable tying the cord down after it comes out of the coil, ensuring
the cable is not at a very tight angle to the exit point, you will
prevent any damage in this area.
Remember A.I. coils can get a little noisy due to
ground conditions so the slower the better. We hear of people using
little flags or coloured spray to mark targets heard when on a run to
minimize the times they get on and off the bike. Having a handheld unit
close will help you identify the target quickly and if you work with a
partner then one can patch find and the other can retrieve the signals
1. DD PRO
DD PRO operation hints & tips
The DD coil has a blade like search pattern into the
ground along the length of the coil so the overlap of your sweeps should
be around ¼ of the coil for maximum coverage. Pinpointing with these
large coils is difficult mainly due to 2 things:
- The coil is not shaft mountable so hard to maneuver into place and get into holes
- The coil’s sensitivity is reduced
Having another handheld unit close by will help you recover targets fast.
The DD coil has excellent depth
capabilities and is best used by dragging behind a person as it is very
susceptible to external interference. We have also seen trolleys made to
hold the coil and be pushed around an area. Just remember to use no
metal in any constructions you make. It might be an obvious statement
but we can assure you it still happens by mistake. Remember the slower
you go with these coils the better as due to their size the coils
tracking ability can hinder performance if run too fast. If you
encounter a lot of ground noise from the set up then check that your
settings on the unit match what speed you are running at and slow down!
These are great tools to help you cover the ground and can lead to great
ANTI-INTERFERENCE (A.I.) operation hints & tips
This is the coil of choice when hunting the Salt Lakes
or dragging the coil behind a quad bike. It has good sensitivity
compared to a DD of similar size and has the ability of punching deep
into the ground. As mentioned in the DD section of this coil it is not
the tool to use when pinpointing so a smaller handheld coil would be
recommended for this. As these coils are fully epoxy filled (potted)
they are very robust and rigid so can take some hard work however the
cable entry point on the coil is the most precious part. They have a
similar coverage area as a DD so a ¼ overlap is recommended and a slow
travel speed is best. Running the coil in standard DD settings on the
later model detectors will ensure the coil performs as it should.
Remember the most responsive area of the coil is the centre spine so
with experience you will be able to master this coils ability.
- Great for deep searching
- Very robust coil
- Good for open terrain searching
- Great ground coverage
- Good stability when motion is slow
- Best used in drag format
Applicable metal detectors
- Minelab SD Series – Best Suited
- Minelab GP Series – Best Suited
- Minelab GPX series