Terminator-3 metal detector is a convenient metal detector model.Metal detector - a specific tool. Not every user may need this interesting device, but they still want to buy a metal detector or, as some call it, plenty of metal scoop. Of course, you can find and buy a device for yourself, but why, if you can make it yourself with your own hands, using the following metal detector scheme - Terminator 3.

On the Internet you can find a large number of diagrams and instructions for making your own metal detector. hands, but below will be presented one of the most popular variations of homemade devices of this type.


  • 1 Simple and reliable metal detector Terminator-3
    • 1.1 Detection Depth:
  • 2 Assembling metal detector Terminator-3
    • 2.1 Metal detector circuit:
  • 3 Description of the configuration of the metal detector Terminator-3
    • 3.1 Checking the instrument board after final soldering:
  • 4 Conclusion

Simple and reliable metal detector Terminator-3

This version of the metal detector, many called one of the most popular. The inventor of such a reliable device are

developers Yatogan and Radioblaster - both forum users md4u.ru. By the way, on this forum you can find a lot of interesting things for those who want to assemble their metal detector.

When folded, this version of the metal detector does not take up much space.A few words should be said that the adjustment and assembly of this IB device will be very difficult for users who have not done this before. It can be said that even almost impossible. This may scare readers, but in no case should you be scared.

It should just be carefully prepared for the build process, which can be done by visiting the well-known forum md4u.ru.

Detection Depth:

  • Five Russian rubles - 22–24 cm;
  • Pyatak Yekaterininsky - 27–30 cm;
  • Helmet - about 80 cm;
  • Beer can - up to a meter.

Depth is calculated for chernozem with a sensor having 240 mm over the wire. By the way, you can say a few words about the discrimination of this metal detector. The fact is that while many of these devices are able to locate metallic element at a certain depth, but can not find out what kind of metal, Terminator-3 copes with this challenge It can detect most metal objects at the extreme depth of detection.

Assembling metal detector Terminator-3

Metal Terminator 3 can be assembled by hand.To assemble and set up this device you will need to use the following devices:

  • multimeter;
  • oscilloscope;
  • LC meter;
  • generator;
  • frequency meter

Of course, if you purchase the entire set of presented devices yourself, you will have to spend money. But you can try to create virtual measuring complex most based on a regular personal computer. On the Internet, by the way, you can find a sufficiently large number of programs for this purpose.

Metal detector circuit:

Scheme homemade metal detector - in detail and clearly.Terminator-3 metal detector is one of the most popular devices of this type. In fact, it is a typical coin box, which, having undergone some refinements, was able to detect gold, while ignoring other non-ferrous metals.

In addition, although Terminator-3 and a coin box, he is also able to search for scrap metal, for which he will simply have to Introduce into the scheme a special mode of "all metals", since the scheme on which this mode is initially taken missing.

The execution of the scheme is carried out with non-standard use of logic as an OU. Of course, there is a certain minus, which is that unknown to KU chips themselvesand the noise level is higher. You can apply the domestic logic, but you have to put up with a large range of parameters. You can, however, perform a replacement on the domestic sound generator chip, without damage and without additional problems.

By the way, Terminator-3 is comparable in terms of such parameters as the depth and accuracy of target identification with models of branded brands that are in the average price range. If you compare with cheaper branded counterparts, the Terminator-3 overtakes them in all respects. But to make it so, you should assemble the metal detector as it should, and not as it will.

Description of the configuration of the metal detector Terminator-3

How to assemble a metal detector with your own hands?To begin with, it is necessary to draw on the nodes indicated in the diagram, since it is along them that one will have to be oriented later. This is useful in the configuration process. When a transmitting coil (TX) it begins to produce current oscillations. These vibrations come in the form of a meander from the chip MC1.

After that, go to the receiving coil (RX), which also has a current induced by TX and creates a field. On this field, the coil should be balanced with TX. In other words, the RX field must be subtracted from the TX field. For this you will need a compensation coil (SH). According to different sensors, it appears differently: in the “RING” sensor, the CX is real, in the form of a coil, and in the DD CX sensor - virtual. It should be connected so that the current in it runs in the opposite direction with respect to the receiving coil. By gradual unwinding from the compensation coil, current TX and RX are balanced.

Balancing is controlled by the oscilloscope, which allows to achieve the minimum amplitude at all positions of the handle in turn. Upon reaching a certain point at which the amplitude starts to grow again, act setup loopwhich is made from one of the ends of the compensation coil. Before this, it is necessary to tune the TX and RX in frequency, while the RX is 100 Hz lower than the TX. The coils are tuned to the desired frequency by connecting each of them in turn to an oscilloscope and an instrument generator.

Printed circuit board for the metal detector, which can be bought in finished form.CX frequency is not required. A situation arises in which the balance is disturbed if a metal object appears under the sensor, as a result, a current is running in the RXwhich then goes into the preamplifier, where it is then amplified and fed into sync detector (SD), which, in turn, detects the phases of the incoming signal and outputs everything in amplification channels. Everything is amplified in them and then falls on the MC8 comporator, whose task is to compare the signal levels in the channels, after which the comporator gives permission to trigger the sound generator.

In principle, almost all balancers work this way, albeit with minor differences. The differences, in many respects, relate to the nuances with the detuning of the metal detector from the ground. In Terminator-3 phase adjustment.

Checking the instrument board after final soldering:

In order to inspect the metal detector board after soldering all the elements of the circuit, a number of procedures should be carried out to determine whether the circuit was properly soldered.

To do this, follow these steps:

  • Installation of the metal detector unit is completed.First you need to thoroughly wash the board. from the flux that could stay there when soldering. It is extremely undesirable to leave any excesses on the board, otherwise you will then have to face the unpleasant consequences of your negligence;
  • After that, turn on the power on the board, but not including the sensor;
  • Need to unscrew the handle sensitivity until the moment when there is a constant beep dynamics;
  • Then just one finger touch sensor connector, so that the sound emitted by the speaker, was interrupted for only a second. If this happens, then you can praise yourself, because if the sound is interrupted, then you can be sure that the board was soldered correctly.
  • When the power is turned on, the diode should definitely blink and go out. Otherwise, when the power is turned off, the diode should light up and gradually go out.

Coil and control unit homemade metal detectorA few words should be said about battery discharge indication. It looks like this: the metal detector begins to send frequent signals at regular intervals. In this case, the diode should be constantly on, and the sensitivity drops sharply.

All settings for the frequency of the metal detector should be made with the same cable with which the device will be used later. After the user has made all the necessary settings for the frequency, in no case can he change the cable length.

Above is a picture that describes the sensitivity of the device. Some data are given on several materials that can be detected by this detector.


In principle, it is not at all difficult to assemble such a metal detector; Yes, it may take a lot of time and effort. and funds, but there are a number of advantages that the user gets as a bonus, who has collected this metal scooter.

How do we work the metal detector?Terminator-3 is a very powerful device when compared with branded models. metal detectors, and given that it can be done with your own hands, this makes it even prettier and is preferable.

Of course, it will be much more difficult for the user to assemble such an instrument if he does not have the proper experience. But there are always manuals and instructions for beginners who will be able to find there a lot of interesting information for future work with electronics.