CREDO DDM Metal Detector User Manual

CREDO DDM

metal detector

User Manual

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Table of contents.

1. General description – page 3, 4

2. Assembly & Preparation – page 5

3. Controls – page 6, 7, 8

- DDM – Definite Discrimination LED Meter – page 6

- Discrimination Control – page 6

- Ground Balance Control – page 7

- Threshold and Auto Mode Control – page 7

- Sensitivity Control – page 7

- Volume Control and Power On/Off switch. – page 7

- Multi Tone Control – page 7

- Mode (Iron Rejection) toggle switch – page 7

- Battery Test toggle switch – page 8

- Recovery Mode toggle switch – page 8

4. Operation – page 8, 9, 10

- If you are a novice in the hobby or a child – page 8

- If you have some experience, but still not on a professional level –

page 8

- If you are a professional or have extensive experience with metal
detectors – page 8

- Full Manual Set Up – page 8, 9, 10

- All Metal Mode – page 10

- Discrimination Mode – page 11

- Pinpointing – page 11

5. Special Modes of operation – page 11, 12, 13

- Discriminating Ground Minerals in severe mineral conditions

page 11

- Discriminating all types of hot rocks and metallic ore – page 11

- Discriminating salt water on tidal beaches and salt water lakes –

page 12

- Discriminating all large metal objects leaving only the
Smaller ones.
Special gold nugget hunting tune – page 12

- Discriminating all small targets and leaving only larger
metal objects – page 13

6. Tips – page 13, 14

7. Care of CREDO DDM – page 14

8. Guarantee – page 14, 15

9. Technical specifications – page 15

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10. Troubleshooting – page 15, 16

General Description

The CREDO DDM is an Analogue Induction Balance (IB) metal detector
that operates in the very low frequency (VLF) range and it is designed for
use on all Inland Sites and Tidal Salt Water Beaches. It may be used in
any of the three basic modes of operation - Auto, All-Metal or Discriminate.

The CREDO DDM is designed to be a general-purpose metal detector,
capable of finding both small and large targets at extreme depths.

The standard coil supplied is the 13”DD and this is ideal for general
searching operations.
There are 4 different DD search coils that can be used as accessory with
the CREDO DDM.

DD shape search coil range.

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- 13"DD at 6kHz
General search coil designed for higher detection ratio of small, medium
and large targets in normal search conditions. It exhibits greater depth than
any other DD search coil made by other competitive brands. It detects
18mm coin at 28 cm with very loud signal responses.
Due to large search area it will find more targets for shorter period of time
compared to smaller search coils. Not suitable for mineralised conditions
due to high probability of producing multiple signal responses.
Extend of detection dept not fully tested yet.

- 10"DD at 7kHz

It could be the best general search coil that you’ll ever need. It exhibits

excellent dept and discrimination in most conditions. Very efficient in
detecting small targets at great dept. Very fast in isolating individual
targets. It detects 18mm coin at 28cm with very good signal response.
Extend of detection dept not fully tested yet.

- 10"DD at 18kHz
Specially designed for gold nuggets and small targets at great dept.
Extend of detection dept not fully tested yet.

- 7"DD at 8kHz
General search coil designed for quick scan of new detecting fields and
areas. Very good for searching narrow spaces, holes and ditches. Best
suited for small and medium targets in contaminated areas.

Each coil is tuned to a slightly different frequency within the design range,
to minimise interference from other Nexus detectors. Performance values
for all Nexus detectors will be identical.

To obtain the best results with the CREDO DDM, as with all metal
detectors, it is essential to understand the settings and operation of the
detector.

The Auto mode of the CREDO DDM will provide exceptional quality results
in the hands of every user, regardless of their experience with metal
detectors. With the CREDO DDM everyone can enjoy the benefits of the
deep seeking Nexus technology, both novice and professional alike.

As a general rule the best results will always be obtained when the CREDO
DDM is properly set in manual mode. Therefore users will need to practice

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and experiment in order to obtain the best possible results on any particular
site. All sites and soils are different and settings that will give good results
on one site may be less successful if used elsewhere. The CREDO DDM
is designed to detect the very deepest of targets and operates near to the
limits of what is achievable with induction balance.

Assembly & Preparation

The CREDO DDM is supplied boxed and ready for quick assembly by
simply attaching the two lower stem poles to the top one, tightening the
collars and attaching the coil to the lower stem section, using the plastic
bolt and friction washers supplied and tightened by hand so that coil is held
at the correct angle to the stem; the coil cable plug is inserted to the socket
in the control box and then tighten the knurled ring, taking care when
winding the cable around the stem that the cable is not strained.

The centre stem pole is of the same tube diameter as the top one and can
be left off in circumstances where a short stem is needed; it is meant for
use on steep sites, river banks, caves, ditches and similar conditions. This
configuration is also useful if the CREDO DDM is to be used by children
and makes it a good family metal detector that can be used by anyone in

the family.

The CREDO DDM is supplied with a drop in battery holder that can be
used for all types of AA size batteries, (alkaline or rechargeable); a
charging socket is provided to the battery box for connecting a charger unit.
To insert or change batteries remove any three of the thumb plastic screws
from the base lid of the battery box (the battery box is below the arm cup at
the top of the detector stem) and loosen the fourth screw. Turn the cover to
the side. Insert the 10 batteries, in their correct alignments, into the plastic
holder and make sure that all the terminals have a good electrical contact.
Locate the battery holder into the compartment, ensuring the connecting
terminals of the battery holder are in good contact with the two electric
spring loaded terminals behind the recharge socket. Do not over-tighten the
plastic thumb screws when refitting.

If you wish to use headphones (highly recommended) connect your
available set to the 6 mm jack socket on the battery box. The CREDO DDM
has an internal loudspeaker so headphones are not absolutely essential.
For any headphones that have a volume control, ensure that this is set to

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MAXIMUM and use the CREDO DDM Volume knob on the control box to
set the volume level.

Controls

The CREDO DDM has six rotary control knobs and three toggle switches
(two located on the front panel of the control box and one underneath the
control box).

DDM – Definite Discrimination Meter

The DDM meter is based on LED technology and provides a reliable visual
discrimination analysis in All-Metal Mode and Iron Rejection Mode. The bar
will light RED for non ferrous targets and will not indicate Iron targets.

Discrimination

This knob sets the level of the discrimination. Rotating the Discrimination
knob clockwise (from 0 to 10) will INCREASE the level so that Iron is
increasingly not detected (but high settings will result in the loss of
potentially good targets). Generally, the discrimination level should be set