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Operating manual

Lorenz Detecting Systems GmbH

Metal Detectors for professional, industrial and

security applications

Röpkestrasse 12

D - 30173 Hannover/Germany

Tel : +49 (0)511 5510670

Fax : +49 (0)511 5510671

mail@metaldetectors.de

www.metaldetectors.de

www.deepmax.com

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Declaration of conformity /

E MC directive

The following metal detector

LORENZ DEEPMAX X3

Correspond to the following EC requirements:

EC-EMC-directive version 89/336/EEC

The LORENZ DEEPMAX X3 series are found to meet

the specification requirements detailed, when tested

to the customers/ specification requirements.

Compatible norms are in particular

Test Specifications & Categories

Emissions EN61000-6-3:2001

Immunity EN61000-6-1:2001

Refer to certificate of testing No: E41105 Phönix Testlab

If any changes are made to the above mentioned appliances without

consulting Lorenz Detecting Systems GmbH this declaration becomes invalid.

Date: 24.11.2004

Signed: _____________________________

Lorenz Detecting Systems GmbH

General Management

Lorenz Detecting Systems GmbH · Röpkestr.˝12 · 30173 Hannover · Germany

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The LORENZ DEEPMAX X3 is one of the newest develop-

by a specially developed, LC Display and a minimum

ments in the field of Pulse GBS metal detectors. It is

amount of controls of which only one reset button will be

probably one of the most sensitive and stable metal

necessary to operate during work. At the same time this

detecting devices of its kind presently available. The LORENZ

detector model offers a number of features which are new

DEEPMAX X3 is the result of many years of research and

for a pulse metal detector. Quality electronics and very

development. A lot of efforts have been put into making

special designed electronic - circuitry produce benefits in

this new product and especially in the new improved metal

terms of easy of use as well as sensitivity.

classification and ground balancing facilities offered with

the LORENZ DEEPMAX X3 series.

The LORENZ DEEPMAX X3 gives a visual indication on the

LC Display for every metal being located. This time delay

The Pulse GBS (Pulse Ground Balancing System) is specialy

reading producing a number between 00 to 99 helps to

suitable for searching at depth. The performance of this

classify metal objects. The target classification circuitry is

electronic device is almost unaffected by salt water, most

only in some cases affected by the size of a metal object

types of mineralised grounds or temperature changes.

and therefore identifies small coins as well as large pieces

Specially designed electronics cancel out signals from the

of metal. The LORENZ DEEPMAX X3 also offers a sophisti-

ground. The LORENZ DEEPMAX X3 is therefore a reliable

cated and refined ferrous / non- ferrous target analysis

tool to locate metal objects at great depths even under the

which works more stable on difficult soils in conjunction

worst environmental conditions. A new improved circuit

with the 26cm or 35cm double D search coil. The Detector

design suppresses interference from power lines and a

also emits an audible sound by way of either a speaker or

power pulse technique produces very accurate signals to

headphones. Detection depths achieved (in air tests) are

obtain very high detection depths.

almost the same in many types of soils and therefore

considerably higher than those possible with standard

The LORENZ DEEPMAX X3 is a high quality specialist

pulse induction or sinewave VLF - TR Detectors.

Detector and it is designed to be used with both, small or

large coils. Large coils offer extreme depth capabilities for

The DEEPMAX metal detectors are often recognised as

big metal objects because of the strong and deep going

representing some of the highest quality and newest

magnetic field produced. Small coils are preferably used

developments in professional metal detecting equipment.

while searching for small objects like single coins or gold

nuggets.

We as a manufacturing company always try to keep the

highest standard on our products, therefore alternations

This model offers a great range on non-ferrous metal

of the design, specifications as well as the availability subject

objects in general. A very simple operation is guaranteed

to change without notice.

1. Safety information

For reasons of safety it is advisable to read this

manufacturer of the LORENZ DEEPMAX X3 should

operating manual first before turning the Lorenz

be used.

DEEPMAX X3 on. Special attention should be paid to

the following notes.

When digging for metal objects war material could

also be found. Precautions should be taken in advance

Check out, if the plug-in type charger supplied with

especially when big objects have been located.

the LORENZ DEEPMAX X3 fits with the AC mains of

your country. The AC plug of the recharger is inter-

Special kinds of mines could be triggered by the

changeable and therefore can be used at any countries

strong DC magnetic field produced by the search

mains. See chapter 7 for more detailed information.

coil. Special versions for military use are also available

The supplied recharger will work at AC voltages of

on request. Persons with implanted pacemaker or

90 V-264 V (see label).

other sensitive device should not approach to the

field of the search coil. Please understand that we as

Damaged connecting cables or search coils should

the manufacturer of the LORENZ DEEPMAX X3 can

no longer be used, because of possible electrical

not be made liable for any kind of damage caused

shock.

by or in conjunction with our products.

To avoid short circuits, wrong polarity or electrical

Design and specifications subject to change without

shock only spare parts and accessories offered by the

notice!

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2. Function

The LORENZ DEEPMAX X3 is based on the non- motion;

an audible signal either by headphones or built-in

Pulse GBS (Pulse Ground Balancing System). Short and

loudspeaker when a metal is in the near of the field of

intensive magnetic pulses are emitted by means of a

the search coil.

search coil first. Those magnetic pulses produce eddy

currents in conducting materials like metal objects for

Eddy currents produced in a metal object by means of a

example. Said eddy currents will be kept in a metal object

pulsed primary field, will die away differently depending

and will die away after the magnetic pulse emitted by the

on the conductivity of the metal object. The classification

search coil has turned off. This is the reason why it is

circuit therefore gives a visual time delay reading for the

possible to detect those eddy currents during the time

eddy currents received over a certain period of time. In

delayed receiving phase by means of the same search

addition a ferrous / non- ferrous indication for every metal

coil which now acts as a receiving coil. A rather complicated

being detected is working when a double D coil is in use.

electronic circuitry is necessary to detect those tiny voltage

This gives further information on the probable kind of

changes and has to separate that particular signal from

metal being located as well as the audio sound emitted,

interference also received. The signal has to be amplified

which makes it easy to predetermine the exact place and

to drive a voltage controlled oscillator (VCO), which emits

the size of the buried metal object.

2.1. Advantages

The Pulse GBS principle has got the advantage of using

depth capabilities for both ferrous and non-ferrous metal

large diameter coils and high transmitting power. This

objects when the Ground Balancing System is in use. Other

is especially necessary when searching at depth. Frame

systems often suffer from ground effects which reduce the

mounted cable coils of different size and shape can be

depth range in the ground. The LORENZ DEEPMAX X3 will

connected to the LORENZ DEEPMAX X3 without any

be able to locate objects at almost the same depths either in

adjustments.

most types of ground or "in air tests". The high sensitivity of

the LORENZ DEEPMAX X3 to non- ferrous metal objects like

A special adaptation circuit has been added to the

gold, silver and copper together with the new target analysis

Detector to suit with different coil systems automatically.

make this detector an outstanding device for many different

This ensures extreme depth capabilities with any coil

locating purposes.

connected. When enlarging the search coil diameter the

sensitivity to bigger objects will also rise. At the same

The LORENZ DEEPMAX X3 was developed to provide a

time smaller objects will be located less sensitive. This

number of features including high sensitivity and stability

is particularly desirable when locating large objects while

together with easy operation. The amount of controls was

ignoring small bits. Large coils offer very high detection

therefore reduced and a calibration of the Detector to our

ranges. Even in difficult soils where magnetic iron oxides

factory settings was also made to guarantee best results in

are present the LORENZ DEEPMAX X3 will offer extreme

the field:

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l highly sensitive to all kinds of metal

Please ask for details. The necessary hard- and

l stable operation on mineralised ground or salt water

software is in preparation. Further informations are

with Pulse Ground Balancing System

available on request.

l reliable / simple operation

External Datalogger and software can also be

l exact pinpointing with large coils

connected. Further informations are available on

l very easy and effective detection of large areas

request.

l rugged, refined mechanical construction

New computer aided search system with LC Display

l a variety of search coils are available for different

and new functions.

detection purposes

Signal strength bar graph, time delay reading (derived

l automatic adaptation of different coil sizes to the

from the eddy currents of the objec's size, conductivity

electronics

and permeability), ferrous / non-ferrous icons, battery

l small unwanted metal objects can either be

condition and the mode settings are displayed

identified or eliminated

simultaneously.

l fast audio response speed with voltage controlled

All functions are visuable on a large LC Display, no

oscillator (VCO)

menus to scroll to get to the function to be altered.

l logarithmic audio response and intensity bar graph

New improved searchcoils available.

rading for easy pinpointing

More stable ground balancing functions means less

l battery check with audio alarm tone

interference in urban areas.

l calibrated static (non-motion) target classification

Improved AUTO function which gives with most

with visual time delay reading

targets only one indication instead of two when

l improved ferrous / non-ferrous identification which

ground balancing system is selected.

is less affected by the ground

New GROUND balancing systems with double D

l precisely adjustable audio-threshold

coils gives additional depth to non- ferrous metal

l stable static response (acoustical and visual)

objects.

l waterproof search coils

Automatic false finding computer aided target

l interchangeable rechargeable Batterypack

identification.

l charge electronics with interchangeable AC-plug

for world-wide operation

l frequency control for interference elimination

l automatic push button retuning facility

l different Delay and Sensitivity settings to eliminate

small objects or for easy pinpointing

l extreme detection depths for very large metal objects

l optimal performance for the detection of small objects

like coins or other non-ferrous objects as well as for

bigger objects buried deep.

l single or dual induction balanced or differential coil

designs can be used.

l Multi sensor detection (MST) with several searchcoils

working at the same time without interfering each

other. Please ask for details.

l Built-in Datalogger comes with every DEEPMAX X3.

2.2. Applications

The LORENZ DEEPMAX X3 was developed for

LOR E N Z DEEPMAX X3. It is possible to eliminate

professional search and locating applications.

some unwanted objects like nails and foils or to

A variety of search coils can be connected to this

identify them as being small unwanted objects

metal detector. Large areas can be detected

while searching for bigger and deeper objects. In

effectively especially with frame coils. Saltwater,

conjunction with small coils the LORENZ DEEPMAX

most types of ground or temperature changes will

X3 is a great tool when searching for small objects

only slightly affect the detection range of the

deep in the ground.

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3. Controls on the front panel

ZERO-pushbutton

The ZERO push button is the most important control

Position 1, 2 and 3 offers an intensity intensity bar

as the whole electronics, including the discriminator

graph reading which works in parallel with the audio.

and the audio will be retuned when pressing this

The more the search coil approaches to the located

control for about 1-3 seconds. During that time no

metal object the higher the indication on the meter

metal should be in the direct field of the search coil.

and the higher the frequency of the audio is.

To retune simply hold the search coil in air horzontaly

Position 1 is an all metal mode which offers the highest

and away from any metal objects while simultaneously

sensitivity for every kind of metal and all object sizes.

pressing the ZERO button for about three seconds.

It should be in use when locating with small searchcoils

There should be almost no signal indication on the

and weakly mineralised soils like sand for example.

meter after having done this.

While turning the detector on with the POWER button,

Position 2 is selected while pressing the DELAY button

the electronics will automatically retune itself for five

again. This Position is mainly in use when locating with

seconds. The previously tuned tick-rate (AUDIO-control)

frame coils on weakly mineralised soils. This position

should be audible, or silent when the AUDIO-control

offers a very high sensitivity as well. Only the sensitivity

was turned to the left. With this button the present

to thin foils and coins will be reduced in this position.

audio tick-rate can always be recalled during operation

while pressing it for one second. When changing the

Position 3

search coil the ZERO push button has to be pushed

The LORENZ DEEPMAX X3 offers in this position less

down for about 3 to 5 seconds to retune the electronics.

sensitivity than in position 1 or 2. In most cases very

small pieces of foil or very small coins will no longer

SENS button

be detected. At the same time the LORENZ DEEPMAX

With the SENS- function control three different sensitivity

X3will work slightly more stable.

settings LOW; MED; HIGH (Low, Medium and High)

Iron, copper or silver objects will suffer from a small

can be selected by the operator. The current setting is

loss in sensitivity. Thin gold or silver plates will be

indicated near the bottom on the left hand side of the

detected less sensitive or can be even ignored. This

display.

position is particularly useful when searching for bigger

Different sensitivity settings can be selected by the way

objects with a limited detection range while ignoring

of operating the SENS button several times.

some smaller pieces of metal. When the universal

cable coil 8m or 12m has got more than three windings

DELAY button

the DELAY position has to be changed to position 2

Three different DELAY settings can be selected by the

or 3 to ensure best results.

way of this control. The selected setting is always

displayed at the bottom on the right hand side of the

Display.

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GROUND button

audio or on the display. The GROUND2 channel

Ground Balancing System GBS

makes sense when locating a few metal objects with

a similar signal response as magnetic soils like some

The GROUND push button works in konjunction with

bronze or iron objects for example. Otherwise some

the GROUND 1 and GROUND 2 controls in order to

of these items could be almost completely masked

compensate or balance heavily mineralised soils

or give a much weaker indication. In many cases

containing plenty of magnetic iron oxides.

however the GROUND1 channel will be sufficent.

Single (hot) stones or certain iron objects can also

After having connected different searchcoils or altering

be completely eliminated/ canceled by the way of

the FREQ.uency control it might be necessary to

these controls. To tune these controls correctly please

retune the GROUND- controls again. If changing

continue as follows:

ground conditions are expected the 35cm double D-

Do only select the GROUND1 or GROUND2 function

coil should be in use. Any time a different GROUND

if strong signals with a long duration produced by

or DELAY position is changed by the operator the

the ground or many false signals from single stones

electronics will retune itself automatically while a

appear. The selected Function will be displayed in

flashing GROUND or DELAY icon will indicate this

the right hand side on the bottom of the LC Display.

tuning time. During that time (approximately 5

When pressing the same button again the next Position

seconds) the searchcoil should be hold away from

namely GROUND 2 or three is selected.

metal objects and at least 100cm over the ground.

Turn on the GROUND1 function. Please also make

AUTO / LOG button

sure that the AUTO function is turned off! Before

When pressing this button the AUTO sign in the

starting to tune the ground balancing facility make

middle of the LC Display comes on. The Detector

sure that the LORENZ DEEPMAX X3 is tuned with the

works very stayble and is capable to suppress signals

ZERO push button in the air first.

caused from weakly mineralised soils or temperature

changes. A slow moving speed of the searchcoil over

The connected Searchcoil therefore has to be hold

the ground or target has to be provided to find metals.

horizontaly 1 to 2m above the ground while

While resting over the object the audio and meter

simultaneously pressing the ZERO push button for

indication disappears.

approximately 4 seconds. The coil can be lowered to

This so called Motion function should only be

the ground or can directly be put on a magnetic stone

selected when working with smaller coils (up to 45cm

afterwards. An audible signal will be produced by the

diameter) as deeply buried targets at certain depth

way of the loudspeaker or headphones. Leave the

might also be canceled by the AUTO / Motion-

coil at the same place and try to alter the position of

function. That is the main reason why it is not advisable

the corresponding GROUND1 control in order to

to turn on the AUTO function while working with

minimize the signal. The ten turn control therefore

large frame coils.

has to be turned to either the left or right direction.

When suffering from week ground signals or a drifting

When having found the point with the lowest

audio in the GROUND2 Mode and double D coil for

indication, leave the control at this position. (While

example, the AUTO-function should be selected. If

further moving the control a signal would appear

the signals from the ground in different DELAY modes

again). When raising the coil in the air or lowering

still can not be canceled the ground balancing system

it to the ground or the single stone, the LORENZ

should be selected with the GROUND button. The

DEEPMAX X3 should be silent. If in any case a signal

built- in datalogger can also be turned on and off

is produced this could be derived from a metal object

with this button. This optional function will store the

signals produced by the detector and will genertate

in the ground which interfered with the tuning process.

pictures with additional hard- and software. This

The whole tuning procedure therefore has to be

optional function is in preparation and therefore not

repeated at a place with no metal.In extremely

working with the machine so far. Please ask for

mineralised environment like basalt rocks for example

availability directly at the manufacturer of the LORENZ

a small distance 5-10cm between the ground and the

DEEPMAX X3. So far additional dataloggers may be

coil should be maintained mainly during the tuning

connected to the datalogger jack.

process (when lowering the coil to the ground).

The tuning process of the GROUND1 and GROUND2

POWER button

circuit is the same. Simply select GROUND2 with the

After having connected a fully charged battery to the

GROUND button and repeat the same procedure.

POWER- jack, the LORENZ DEEPMAX X3 can be turned

When GROUND3 is selected both GROUND channels

on with this push button.

are selected simultaneously and the channel producing

The electronics will automatically tune and reset itself

the stronger signal will be indicated by the way of

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for five seconds and the detector runs through a display

Any metal object detected will give a specific number

check sequence with an attention icon flashing at the

(00 to 99) if the signal is strong enough to make a

same time. During the retuning process the searchcoil

reading possible. Therefore a certain intensity of the

should be held at least 1m over the ground and far away

target signal is necessary for a time delay reading.

from metal objects. Each time the battery is disconnected,

The number simply appears when a reading was

the LORENZ DEEPMAX X3 has to be turned on with the

possible. The indication will be stored as long as the

POWER button again. The selected settings will be stored

search coil is over the target and turns off when the

even if the Detector is turned off and on again. When

search coil passes the target.

planning to store the LORENZ DEEPMAX X3 please make

FERROUS / NON-FERROUS icons

sure that no connectors are connected to the control

box or battery.

This function does only work with the 26cm or 35cm

double D coil. Ferrous metal objects like iron for example

AUDIO threshold control

produce a FERROUS indication at the top of the display

With this audio control the tick-rate of the audio can be

and Non-ferrous metal objects like gold silver or copper

selected. The ZERO button can be hold simultaneously

will result in a NON- FERROUS icon indication when

while turning the audio control. The initial tick-rate can

the searchcoil is moved over the target. The two icons

be altered from silent to a low frequency ticking tone.

will turn off if no metal is present or no double D coil

For most applications this control can be left in mid-

is connected. This identification facility is tuned to the

position. In this position the built- in loudspeaker will

ground with the GROUND2 control as well.

give one tick every 1- 2 seconds, after the detector has

INTENSITY / signal strength bar graph icons

been retuned with the ZERO button.

The signal strength will be indicated by the way of a

Note: The AUDIO threshold control also acts as a sensitivity

large bar graph in the middle of the LC Display and

an audio response from the speaker or headphones.

control. When it is set to the left the detector will respond

up to 60 % less sensitive than at the mid- position. The

ATTENTION; ARROW; AERIAL icons

detectors sensitivity may also be slightly increased when

These icons will work together with the built- in

using a higher threshold-setting than the mid- position.

datalogger which will run on an optional hard- and

FREQ. - frequency control

software which will be available in the future. Further

With this control the preset operation frequency of the

informations are available on request.

LORENZ DEEPMAX X3 can be altered. This is mainly

BATTERY alarm

necessary when searching near power lines, which cause

low frequency interference. The performance of the

Low battery condition will be indicated by a pulsed

detector won't be affected by changing the position of

beep sound every few seconds the LORENZ DEEPMAX

this control, but the amount of interference can be greatly

X3 has to be turned off when this sound appears to

reduced by doing this.

avoid damage from the batteries.

LC Display

BATTERY jack

The LC Display has got different icons and indications

This jack is located close to the COIL jack. The plug

which are displayed at the same time.

of the supplied battery pack has to be connected with

this jack. The operation time of the LORENZ DEEPMAX

BATTERY icon

X3 on a fully charged battery pack at normal

temperature range is approximately 6 to10 hours

The battery condition will be displayed on the bar graph

depending on the coil connected.

with 5 bars located in the middle of the display. Note:

The battery condition should be checked with a search

COIL jack

coil connected and after a few minuts of operation.

Search coils of different size and shape can be

connected to this jack. The search coils available for

the LORENZ DEEPMAX X3 have got coded connectors

A time delay reading which is mainly derived from the

to adapt the electronics to the coil automatically. To

conductivity, permeability and the object's size is displayed

connect a coil plug to the electronics make sure that

with a specific number on the LC Display. Possible

the plug is fully pushed in the jack and that the sleeve

examples:

is fastened by rotating it clockwise.

(0-20 coin or piece of foil, 30-60 iron, 60-99 large copper

or silver object)

Note: Any connectors should be disconnected when

The indication is displayed as long as the coil is over the

target.

planning to store the LORENZ DEEPMAX X3.

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HEADPHONE- jack

distance between the search coil and target for

The supplied stereo headphones can be connected

better pinpointing. Especially with two persons

to this jack. Any stereo headphones with

operation and large diameter coils the signal from

1/4 inch (6,35 mm) stereo plugs can be connected

the loudspeaker is of greate help for both persons.

to the LORENZ DEEPMAX X3 without any problems.

DATALOGGER jack

The built- in loudspeaker will be automatically

turned off when headphones are connected.

The LORENZ DEEPMAX X3 can either be operated

with a built- in or an external datalogger in order

Note: Special headphone- adapter plugs have to

to record different signal data during operation. For

operation an optional hard- and software kit will

be disconnected when using the loudspeaker.

always be necessary please contact us for availability.

Loudspeaker

This jack therefore offers different signals for further

The LORENZ DEEPMAX X3 has got a built-in

data recording equipment. In conjunction with

loudspeaker on the rear which gives an audible

specially developed software it is possible to convert

signal when the search coil approaches to a metal

stored data to visual Images. Please contact us for

object. The audio frequency will change with the

further details.

4. Operating procedures

Afterwards the Detector will automatically turn to the

Do connect the two shoulder straps to the main belt at

positions which were selected the last time the detector

both sides in the front and one large strap above the

was in use. While pushing the SENS, DELAY, GROUND

battery pack on the back. Adjust all the belts to

or AUTO push buttons several times, different settings

comfortable length and fasten the main electronics unit

will be selected and will be displayed on the bottom of

in front of the operator.

the LC Display at the same time.

Connect the search coil-connector to the COIL jack on

Select mid position for both the AUDIO- and

the left hand side of the electronics unit, and fasten the

FREQ.uency control and push the ZERO button for

plastic sleeve of the connector by rotating it clockwise.

three seconds. If low mineral contents of the ground

Do connect the battery connector to the BATTERY jack

are expected it is sufficient to hold the searchcoil a

which is located close to the COIL jack on the left side

few centimeters over the ground while simultaneously

of the detector by pushing it gently. Hold the connected

pressing the ZERO button for about three seconds.

searchcoil horizontaly and far away from metal objects

Than simply release the button and try to keep the

about one meter over the ground. Set the POWER button

distance between the coil and the ground very

to turn the LORENZ DEEPMAX X3 on. Press again for

constant when searching.

"OFF". At switch ON the detector runs through a display

The pre selected audio ticking sound is audible every

check sequence since all the icons com on and the

1-3 seconds. Alter the AUDIO control for different

flashing ATTENTION icon indicates the retuning process

ticking sound if necessary.

is performed by the electronics at the same time. If the

Important note: With every retuning process one

BATTERY icon displays less than one bar afterwards or

should pay attention that no metal is in the near of

if the BATTERY alarm gives a beep sound every few

the search coil while pressing the ZERO button. It is

seconds, the detector should be turned off again and

therefore necessary to hold the search coil far away

the battery should immediately be recharged with the

from metal objects and the electronics control box

supplied charger. The battery condition is displayed with

itself.

five bars in the midle of the Display continuously during

During operation no metal buckles or shoes containing

operation.

metal parts should be worn. The same with keys,

Note: On the main electronics unit two large aluminium

coins, rings and watches. Every metal carried by the

operator can cause false signals, especially when they

plates are located, which get warm during operation.

are located near the field of the search coil. Therefore

Please make sure that the heat can disappear and that

the electronics control box has to be carried far away

the aluminium plate is not covered with a jacket or other

from the search coil, this is especially important while

materials to avoid overheating the unit or burn your

searching with the large frame mounted coils. Never

skin. The unit therefore has to be looked after during

use any regular metal screws except thin V2A or V4A

operation and should not be used in sealed containers.

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steel screws with less than 6mm diameter and 50mm

from metal objects. When resting the coil over the target

in length when building frames for the cable coils.

the AUTO function will cancel out the signal after a short

time. In the following chapter operation procedures for

The loudspeaker will give one "tick" every 1-3 seconds

highly mineralised soils with ground canceling controls

after having retuned the detector correctly with the

GROUND1 and GROUND2 are explained.

ZERO button. The "ticking-rate" can be individually

tuned from silent to a low frequency threshold tone

Large diameter coils like the frame mounted cable

with the AUDIO control. This pre-set audio tone will

coils should be hold at heights of (10 to 60 cm) over

be recalled every time the ZERO button is operated.

the ground to ignore magnetic mineralised ground

As the LORENZ DEEPMAX X3 offers it's highest

or small unwanted metal objects. Those coils should

sensitivity with correctly tuned electronics, one should

be moved slowly without any jerky movements,

check the threshold tone from time to time during

parallel to the ground and at constant height.

operation. Although a constant ticking sound is not

When many small unwanted bits and pieces or very

always achievable, a threshold tone with a "ticking-

strong signals are expected it may be advisable to

rate" will give the operator the information that the

select a higher delay setting selected with the DELAY

detector works with its highest sensitivity.

button like DELAY3 for example.

Especially for target classification and ground balancing

In position 3 and specially while using large diameter

purposes the electronics need to be tuned for best

frame coils the sensitivity to very small objects

results (see chapter 5).

significantly decreases. This is in many cases desirable,

The detector is now ready for use and will indicate

although the general sensitivity will be less. The

a metal object immediately with an audio sound

simplest way to ignore small metal objects is to

emitted by the way of loudspeaker or headphones.

increase the distance between the search coil and

The audio frequency will rapidly rise and attains its

the ground. Simply raise the loop and it will still be

highest frequency when the search coil is directly

possible to locate those deeper bigger targets. Be

over the target. The centre of the search coil is the

always sure that there is a sufficient distance between

part with the highest sensitivity. Even in the direct

the detector or battery and the frame coil when raising

near of the target frequency changes make pinpointing

the loop.

possible.

Note: The LORENZ DEEPMAX X3 metal detector has

The detector works with highest sensitivity in position

DELAY1 for small coils and DELAY2 for large frames.

to be retuned with the ZERO control every time a

When changing the search coil the electronics need

different coil has been connected. During operation

always to be retuned via the ZERO button. When lowering

only very few threshold corrections are necessary.

the search coil to the ground an audio sound may

appear, this can be canceled out by pressing the ZERO

In position DELAY2 and specially in position DELAY3

button again. The distance between the search coil and

the LORENZ DEEPMAX X3 works with less sensitivity

the ground has to be kept at a constant height when

for thin foils and small coins. Position DELAY1 offers

searching afterwards. When working with small searchcoils

the greatest sensitivity especially for very small non-

of up to 45cm diameter it is also possible to select the

ferrous metal objects like coins and nuggets. To record

AUTO function with the AUTO button in order to retune

the conductivity (derived from the time delay of the

the electronics to changing ground conditions

eddy currents produced by the targets) or to

automaticaly during operation. The search coil therefore

distinguish between a ferrous and non-ferrous metal

has to be moved at constant speed to achieve a signal

targets please refer to the next chapter.

5. Operating procedures II

This chapter is a kind of summary how to proceed

A specially developed electronic circuit makes time

with the LORENZ DEEPMAX X3, when locating metal,

delay readings possible which are directly displayed

while using the two target classifications, intensity

on a scale of 0 to 99. Those so called conductivity

reading and the audio signal.

readings are only known from VLF TR-Machines but

It is therefore in some cases possible to predetermine

not from metal detectors based on the Pulse-GBS

the exact position, the detection depth as well as

principle. In general these readings are based on

the kind of metal located.

object's size, conductivity and permeability of the

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target and therefore named time delay readings for

to avoid false signals caused by metal parts of the

simplicity.

electronics control-box.

Please proceed as described in chapter 4 and follow

these additional instructions listed below.

The search coil should be held at a constant height

Two person operation is necessary when using frame

while searching. In many cases it is advisable to

mounted coils. The coil has to be hold with two

search in a systematically manner with a certain grid

adjustable carrying straps at a constant height over

which can be marked on the ground for example.

the ground. The search mode can now be selected

The small (26cm ; 35cm ; 45cm) diameter search

with the DELAY or GROUND button. Before starting

coils can be supplied with a telescopic S- pole which

to search it is advisable to adjust the threshold of the

is held at constant height and in parallel to the ground.

audio.

The coils have to be moved from side to side with

For most detection purposes the AUDIO and

overlapping tracks to detect even the smallest metal

FREQ.uency control can be put to the marked mid-

pieces which can sometimes only be detected in the

position.

centre of the search coil as this is the most sensitive

When having done this it is important to retune the

part. Although the response speed of the LORENZ

electronics with the ZERO-control. Proceed as

DEEPMAX X3 is very fast, the search speed should

described in chapter 4 and hold the search coil or

not exceed 2 meters per second.

frame over the ground while pressing the ZERO

button for about 3 to 5 seconds.

When a metal object is located try to find the place

When lowering the search coil to the ground an

with the strongest signal which means highest

increasing ticking-rate of the audio can be audible in

indication on the INTENSITY bargraph and highest

some cases, especially when DELAY1 or DELAY2 is

audio frequency. Size, shape and depth information

selected.

can be derived from the audio sound in some cases

with some experience. Small objects like single coins

This can either be generated by a metal object or

will be indicated with a short and intensive signal

mineralised ground. When expecting mineralised

when a small coil is used.

grounds with high iron oxide content the search coil

can simply be raised again, (10 to 50 cm) depending

Coins and nails and very small pieces of metal will

on the coil and the LORENZ DEEPMAX X3 can simply

cause two indications when passing them with a

be tuned to the ground conditions while holding the

frame mounted search coil (1 m x 1m) for example.

coil at a constant height and pressing the ZERO button

This is mainly because those small objects are out of

for a second. Pay special attention to metal objects

the range of the large coils and therefore will only

in the near of the search coil which may cause false

be indicated at the edges of the frame coils and only

signals and therefore a false retuning process.

when they are very close to it. Large metal objects

will give an extensive signal with a longer duration,

Note: It is always advisable to carry the detector

and therefore can easily be identified.

Deeply buried metal objects will generate a weak

and the separate battery pack as far away from the

and slowly increasing audio sound and intensity meter

search coil as possible. This is absolutely necessary

Signal intensity

ËË

small object at the surface

large object buried deep

medium size object

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reading. Objects which are closed to the surface

it is of great help to use an additional smaller coil when

generate a strong and rapidly increasing signal.

pinpointing a target. The centre of the search coil is

always the most sensitive part.

Large objects will cause a signal with a long duration

When having found the place with the strongest indication

especially when located with large frame mounted

the time delay indication will come on with a number

cable coils. For example a metal box 20cmx20cm can

when the signal is strong enough. When double D coils

give a signal of up to 6 m in length when passing

are in use an additional ferrous / non-ferrous indication

with a (2 m x 2 m) coil for example. It is therefore

will appear on the LC Display. Therefore the GROUND

necessary to find the center of a buried object by the

2 control has to be tuned properly as shown in the next

way of the audio and INTENSITY bargraph. This is

chapter to avoid false indications produced by the

achieved by moving the coil from different directions

ground. Larger ferrous metal pieces will also be indicated

slowly towards the strongest indication. In many cases

as being non-ferrous.

5.1. Ground excluding GROUND 1/2/3

with the lowest indication and leave the control in

These two ground excluding filters can be selected

this position.

with GROUND button and work in konjunktion with

Afterwards the coil can be raised in the air. The

the corresponding GROUND1 and GROUND2

LORENZ DEEPMAX X3 should now be silent even if

controls in order to cancel out signals from magnetic

the coil is lowered to the ground again. If still

soils or single stones with high iron oxide contents.

indications occur it may be possible that the Detector

Even some iron objects can be discriminated/

has been tuned to a piece of metal in the ground.

eliminated by the way of the same controls.

In this case simply repeat the same procedure at a

For tuning purposes please go on as follows. Select

metal free place. The tuning process is the same

the GROUND settings 1, 2 or 3 if false signals from

with the second ground canceling circuit GROUND2

magnetic stones or soils occur. Hold the searchcoil

and could be performed with the GROUND2 control

about 1m over the ground. Press the GROUND

after having turned on the GROUND2 function. The

button repeatedly if necessary until the desired

GROUND2 function was mainly developed to receive

position is displayed on the right hand side of the

signals even from some iron and bronze objects

screen and wait until the tuning process is finished.

producing almost the same signals as some types

When pressing the GROUND button the function

of ground. Both filters could be selected at the same

starts to flash in the display as long as the tuning

time to achieve highest sensitivity for most types of

process is working. A short beep sound will indicate

metal objects when GROUND3 is selected. The

that the detector is ready for use. If the detector has

Detector will distinguish automatically between the

been tuned before you are ready to go searching if

two signals and will use the stronger signal of the

not go on as follows.

two. In most cases however the GROUND1 function

will be sufficient. It is not necessary to run through

Before the compensation to the ground is performed

the whole tuning process every time the ground

the electronics need to be tuned. Therefore be sure

properties changes. It is also possible to alter the

that the AUTO- function is turned off. Firstly the

settings of the two controls GROUND1 and

connected search coil has to be hold horizontaly at

GROUND2 when GROUND3 icon is on the Display

least 1m over the ground in the air where there is

and the coil is lowered to the ground. When changing

no metal, while simultaneously pressing the ZERO

the coil the ground compensation has to be retuned

button for about three seconds. Secondly the

again. If changing ground conditions are expected

Searchcoil can be lowered to the ground or hold

the 35cm double D-coil and GROUND1 position

directly on a magnetic stone. An audible sound will

will be the best choice. When Double D coils are in

appear most likely. When having selected the

use the GROUND2 function works different to the

GROUND1 function the signal can be completely

previous explained single coils. The detection depth

canceled by adjusting the corresponding GROUND1

to many non- ferrous metal objects will be

control to either the left or right direction. When

significantly increased when GROUND2 or 3 is in

approaching to the minimum indication the audio

use with that coil. In some cases however

will disappear. When moving the control further, a

temperature changes

signal will be audible again. Try to find the place

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might cause a drift of the audio and the detector

sensitive. It is even possible to eliminate large ore

therefore has to be retuned with the ZERO button

small iron objects when selecting a special GROUND

from time to time or the AUTO function has to be

setting. Signals will still occur when the distance

selected to cope with this matter. When having

between the coil and the target is too small because

selected the AUTO function some iron targets will

of signal overload. Most metal objects will be detected

respond with a slowly decaying double or triple signal

with almost the same sensitivity as without ground

every time the coil passes a metal object.

balancing circuit. An increase in interferences with

turned on GROUND function due to powerlines and

With turned on GROUND function the LORENZ

radio transmitters will be realized. The amount of

DEEPMAX X3 works with reduced sensitivity. Some

interferences could only be reduced by the way of

iron objects and very few non-ferrous metals with a

changing searchcoils or setting the FREQ.uency control

similar signal response as iron will be indicated less

to a different position.

5.2. Target classification

In order to get further informations from the buried

l Slowly move the search coil from the side at con-

metal object the target classification can be used. The

stant height towards the located target. Try to find

two target classification features offered with the

the centre of the target with the audio signal. As

LORENZ DEEPMAX X3 are based on different working

soon as a certain intensity of the audible signal is

principles. The time delay reading is static therefore

reached a time delay reading will be performed

no motion of the coil is necessary to make a reading

by the LORENZ DEEPMAX X3 automatically. This

00 to 99 possible. This is especially of great advantage

will be indicated with a number between 00 and 99

when identifying deeply buried metal objects with

on the screen.

the highest sensitivity possible. The calibrated target

l Compare the displayed number with the following

classification will directly display the time delay with

table. Therefore the search coil must be held over

all coils connected. The FERROUS / NON-FERROUS

the target on the ground in order to store the

indication is a motion type which will appear with

conductivity value. For better accuracy the

the 26cm or 35cm double D coil connected only

conductivity reading can be repeated. Therefore

when the coil is moved over the target. Weak signals

the coil has to be raised in the air or moved to

which are out of the range of the target classification

the side until the first reading disappears.

can not be identified.

Afterwards the coil can be lowered to the ground

The conductivity reading is very precise. It will be

towards the target until another meter reading is

stored as long as the coil is over the target and will

performed by the LORENZ DEEPMAX X3.

disappear when passing the target with the coil.

Note: The TIME DELAY indication can also be locked

When having located a target proceed as described

in the following steps:

near 00 when very small coins or gold nuggets are

indicated. This target classification will work in any

position and with any searchcoil connected.

Conductivity Possible

meter-reading Metal object

Note: Especially when expecting very strong signals

and mineralised soils at the same time it is often

0-10 coin, ring, ringpull, aluminium-

advisable to hold the coil at a higher distance over the

foil, gold-coin

ground. This will help to ignore magnetic soils, because

10-20 bronze-coins, silver-coins, nickel

the coil is out of the range of the ground.

20-30 softdrink-can, small pieces of

This will increase the performance and accuracy of the

iron

classification circuit and makes it easier to locate and

identify these targets. In most cases however a special

30-50 ferrous metal objects, nails

circuit will suppress the false readings derived from magnetic

50-60 iron-box, weapons made of iron

soils effectively, even if the coil is close to the ground.

60-80 medium sized bronze, copper,

silver-objects

When expecting very deep targets it will sometimes not be

possible to perform a reading because the indication is

80-100 big bronze, copper, silver,

always about 30 to 50% less sensitive than the audio signal

gold-objects

or intensity bargraph.

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Some smaller pieces of bronze may be indicated with a

It is necessary to find the centre of the target. The

time delay reading between 50 and 60 namely the same

search coil therefore has to be crossed directly over

as some ferrous metal objects. At the same time the

the target in order to find the point with the strongest

LORENZ DEEPMAX X3 does not suffer from anomalous

signal. Highly mineralised soils, electromagnetic

effects like VLF-TR- sinewave detectors do. Therefore very

interference from power lines or transmitters can

big ferrous metal objects will not cause a higher reading

course inaccurate conductivity meter readings

than 60 in most cases. If ferrous and non-ferrous metal

especially in urban areas.

objects are simultaneously located by the search coil the

(see chapter 8).

target classification circuitry will display the conductivity

Some nails or longer ferrous objects produce different

of the larger metal object on the screen. The reading may

signals when passing them with the coil.

also lie between the two different kinds of metal.

Note: When expecting heavily mineralised soils it is

The TIME DELAY target classification of the LORENZ

necessary to tune the detector to the ground first as

DEEPMAX X3 will work with all available coils. It is capable

described before.

to identify deeply buried big metal objects and small

objects near the surface. The universal cable coil should

The FERROUS / NON-FERROUS target identification

not have more than three windings (turns) for identification

is of great help when classifying smaller objects in

purposes. It is often helpful to start with "in-air" tests in

weakly or medium mineralised soils at detection

order to see how the detector responds to different metals.

depths between 10 and 70cm.

6. Searchcoils/Accessories

Different search coils can be connected to the LORENZ

The 26 cm search coil is waterproof and therefore

DEEPMAX X3 for special search and location purposes. In

can be used in saltwater for example. Single coins

general small search coils offer great detection depths on

can be detected at 20 to 40 cm even in different

small metal objects while large search coils offer the highest

kinds of ground or conducting saltwater.

possible detection depths on big objects. The possible

detection depths also depend on the setting of the detector,

the kind of metal the shape of the metal object and slightly

on the type of ground below the search coil. The low

sensitivity for small metal pieces in conjunction with the

very high sensitivity for bigger and deeper targets make the

LORENZ DEEPMAX X3 especially useful when using it with

large frame mounted search coils. The maximum detection

depths achievable with a 1m x 1m frame mounted search

coil are very high and can be increased when enlarging the

search coil to 1,5m x 1,5m, 2m x 2m or 3m x 3m. Of course

26cm double D search coil

it will no longer be possible to detect single coins or nails

with those large frame mounted search coils. In this chapter

A specia double D version of this coil with separate

different search coils available with the LORENZ DEEPMAX

transmitting and receiving coils is also available. This

X3 are described. (see chapter 11 for detection depths)

coil makes FERROUS / NON-FERROUS indications

on the display of the LORENZ DEEPMAX X3 possible.

26 cm search coil

This search coil was mainly developed for the location

Note: The electrical properties of the double D search

of very small metal objects which are close to the

coils may change when mechanical tension is produced

surface like coin sized metal objects for example. The

in the coil when being used not

maximum detection depth is limited by the size of the

properly. Searchcoils therefore

object and the coil.

are not covered by warranty

This search coil can be useful while pinpointing large

for that reason.

metal objects which have been located with a frame

mounted search coil before. Deeply buried metal

objects can be out of the range of the small 26 cm

search coil and therefore can only be detected with

frame mounted search coils.

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Those extreme depth ranges on medium sized and bigger

metal objects make frame mounted search coils unnecessary

in some cases. Small items can be eliminated by increasing

35 cm - search coil

the distance between the coil and the ground or while

selecting DELAY2 for example. This 45 cm coil covers more

This highly sensitive search coil has got very good

ground than a 26 cm coil does and therefore makes very

depth capabilities on single coins and medium sized

effective searching possible.

objects. A telescopic pole with armrest (accessory)

Those small objects can easily be identified by the way of

is necessary for any of the small search coils (26 /

the target classification. Coins with a diameter of less than

35 / 45 cm).

15mm should rather be detected with smaller search coils.

Universal cable coil 8 m

This extremely lightweight and easy to transport universal

35cm double D search coil

cable coil offers a variety of different search coils for

Separate transmitting and receiving windings offer

different search applications. The cable coil has to be fixed

more stable operation on soils with changing contents

with tape on a frame which can be made of inexpensive

of iron oxides (minerals) in some cases. Pinpointing

PVC-tubes for example. The following search coil

small metal pieces is easy with this coil, which can be

configurations are mainly useful for the location of metal

used for most search applications. The FERROUS /

objects with a surface of at least 6 cm x 6cm or fist sized

NON-FERROUS target identification does only work

metal objects for example. Small metal pieces like single

with the 26cm and 35cm double D searchcoil.

coins or nails will be indicated with poor sensitivity or will

even be eliminated in some cases because they are out

Note: The electrical properties of the double D search

of the range of those frame coils. It is very easy to cover

a large area with frame coils in a short time. This is

coils may change when mechanical tension is produced

especially useful when looking for bigger deeply buried

in the coil when being used not properly. Searchcoils

metal objects while ignoring those smaller metal pieces

therefore are not covered by warranty for that reason.

at the surface.

45 cm - search coil

The following frame mounted search coils have to be

This search coil can be operated by a single person with

carried by two persons with adjustable carrying straps.

the S-rod-handle. It offers extreme depth ranges on either

The search coil should be hold in parallel to the ground

single coins or bigger objects buried deep in the ground.

at a constant distance of 10 to 60 cm. The electronics

Depth ranges of more than 1 m for a metal object of the

control box should always be carried far away from the

size of a soft drink can (0,33 l) or up to 50 cm on a single

field of the search coil. It is also necessary not to wear any

gold coin with 25mm diameter make this coil interesting

clothes with metal when operating the LORENZ DEEPMAX

for a lot of different search and locating purposes.

X3 to avoid false signals.

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0,67 m x 0,67 m universal cable coil

coil has to be carried by two persons with the supplied

carrying straps.

(3 windings)

The high depth range of the 1mx1m frame coil is

The universal cable coil has to be arranged to a 3

achieved with it's intense and therefore deep going

winding search coil and has to be fixed on a 0,67m x

magnetic field transmitted. The detection depths

0,67m frame made of PVC-tubes for example.

listed in chapter 11 have been recorded with different

Never use any regular metal screws for the construction

DELAY settings. In some cases detection depths in

of a frame! Only V2A or V4A screws wit less than 6mm

wet, conducting ground are slightly higher or lower

diameter and less than 50mm in length may be used

than listed in chapter 11.

to fix the frame. This is the smallest frame mounted

For even higher Detection depths use the 12m

search coil which offers extreme detection depths for

cablecoil which can be arranged similary to the 8m

smaller and medium sized objects. Metal fragments

cablecoil to 1m x 1m, 1,5m x 1,5m and 3m x 3m for

and some coins will still be indicated. The maximum

example.

detection depth is limited below the bigger frames but

higher than with a 45cm diameter coil. This 0,67m x

1m x 1m frame coil

0,67m coil receives less interference from power lines

or transmitters than larger 1m x 1m or 2m x 2m coils

do. (see chapter 8).

1m x 1m universal cable coil

(2 windings)

The universal cable coil has to be arranged to a 2

winding search coil and has to be fixed on a 1m x

1m PVC- tube frame for example.

1m x 1m frame coil with cable inside tubes

Searching with the 1m x 1m frame coil is mainly

This is a very user friendly 1m x 1m coil with the

advisable when looking for fist sized or bigger metal

same electrical properties as the universal cable coil

objects buried deep while ignoring small coins, nails

with two windings as described before. The main

and pieces of foil at the surface of the ground. The

advantage of this particular search coil is its simple

possible detection depths with this particular frame

assembly, which can be performed in a few steps.

coil are very high compared with standard sinewave

The disassembled coil is easy to transport and will

VLF-TR-detectors (see chapter 11). This is one of the

always be ready for use.

reasons why this particular search coil is used for

most professional applications.

The coil cable is protected inside the tubes and

therefore can be used even under the worst

The detection depths are in some urban or areas

environmental conditions. Two adjustable carrying

where a lot of small iron pieces are present even

straps are supplied with every frame coil.

higher than those achievable with much more

expensive magnetometers which can detect ferrous

2m x 2m frame coil

metal objects only. The LORENZ DEEPMAX X3 is

specially sensitive to many non-ferrous metal objects

The universal cable coil has to be laid to a single turn

no matter which coil is connected.

on a metal free frame and has to be fixed with tape

for example.

Large areas can be covered in a short time. Best

This particular search coil covers four times as much

results are achieved with metal objects having a

ground as a 1m x 1m frame coil does. It should only

surface of at least 10cm x 10cm.

be used when searching for metal objects with a

Because of the size of the coil most of the small metal

surface of at least 20 cm x 20 cm pointing towards

fragments will be ignored. However bigger nails can

the coil. Smaller targets will be located less effectively

be identified with the time delay target-ID. Most of

than with a 1m x 1m frame. This is mainly because

the nails and other metal fragments can be easily

it will become more difficult to pinpoint those smaller

eliminated by increasing the distance between the

objects with the large coil. The maximum detection

search coil and the ground. Even at distances of up

depth is very high and can only be increased with

to 50 cm there will only be negligible detection depth

the 12m cablecoil arranged to a 1,5m x 1,5m or 3m

losses when locating large metal objects. This frame

x 3m frame. Very high detection depths can be

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Special cablecoil 12 meters

achieved when locating large objects like several

drums or ammunition deposits or bombs buried

perimeter 1m x 1m (three windings)

deeply in the ground. The 2 m x 2 m frame coil can

1,5 m x 1,5 m (two windings) or

be carried by two persons without any carrying straps

3 m x 3 m (one winding)

(at a distance of about 80cm towards the ground).

This is particularly useful when trying to ignore

Similar to the 8m universal cable coil this large cable

medium sized metal objects which are smaller than

coil can be arranged to three different frame coils by

a horseshoe for example. Coins and nails will no

simply fastening one two or three windings on a

longer be detected when doing this.

metal free frame with tape for example. With the

The 2m x 2m coil acts as a large aerial for medium

largest 3m x 3m frame coil the highest possible

wave transmitters. Therefore smaller frames like the

detection depths of the LORENZ DEEPMAX X3 can

1m x 1m coil will be of better choice when working

be achieved. This is mainly possible because of

in urban areas. The next coil described will be less

specially developed electronics to eliminate low

sensitive in general but won't suffer from

frequency interference and a power pulse circuit

electromagnetic interference of transmitters, power

built- in the LORENZ DEEPMAX X3. The high sensitivity

lines or the ground itself.

for large and deeply burried metal objects and the

simple elimination of smaller metal fragments make

1m x 2m compensated framecoil

these three coils interesting. The shape of these large

coils should be the same as with the other coils

In order to construct this compensated coil the coil

namely round or square. It is also possible to build

cable has to be laid to the figure of the shape of an

eliptical or different shapes but this is only achieved

eight (8) first. The coil cable has to be fixed on a 1m

at the expense of sensitivity.

x 2m frame with a centre part which divides the frame

into two 1m x 1m frames. The cable has to be laid

In urban areas the amount of interferences produced

and fixed twice on the centre part as this is the middle

from power lines will be higher than with smaller

of the eight (8). This type of frame mounted search

coils and therefore again the sensitivity might be

coil is about 30% less sensitive than a 1m x 1m search

reduced. The ground balancing system GROUND1,

coil. This is because of the opposite directions of the

2, 3 should be turned off in some cases using these

transmitted magnetic field. During the receiving phase

large coils because of the same reason. Some

the two coils of the eight do also work in opposite.

companies use these large frame coils with two similar

Therefore interference and some ground indications

coils mounted on each other at a distance of about

are subtracted from each other and therefore

60 to 70 cm the same way as the double frame coil

eliminated.

described before. Anyway it is advisible to keep a

Interference from radio transmitters or power lines

distance of at least 20 to 80 cm constantly between

will be almost completely cancelled. Highly mineralised

the coil and the ground to reduce the amount of

grounds will be indicated less sensitive than with a

ground effects to a minimum when using these very

1m x 1m search coil. This compensated 1m x 2m