This metal detector (FelezJoo PI) is very simple and powerful and I think it is the best system that has ever been given for free to the public.
It is appropriate here to thank the designer (Mr. Hamid from iran).
Then I put the necessary files to build the metal detector and give explanations about it.
The designer of this great system, to avoid unwanted effects caused by the parts and hardware as well as to reduce the size of the system and making it easy for most users, as well as those who have little knowledge of electronics, small parts used .Instead, with an accurate and professional programming, all features are included in the scheme and applied digital.

Features :

Sensitivity
Frequency regulation
Adjustable pulse width
delay
Contrast adjustment
Adjustable back light
Sound setting
Change the type of sound
Iron reject
Target ID (The numerical separation of various metals)
Automatic Balance
Debug
Integ.W ( Set the interval integrator)
Adapting to the ground(Self Adjusting Threshold)
Set the speed sensing

FelezJoo Schematic

FelezJoo PCB

FelezJoo Partlist

Capacitors

——————————————————————————————–
C1………………………. 10uF-16v electrolytic
C2, C3 ……………………….18pF ceramic
C4, C5, C7, C8, C9, C14 ……………………..….100nF (or Code 104) ceramic
C18, C20, C21, C23, C26 ……………………….100nF (or Code 104) ceramic
C6, C12 ……………………….100uF-16v (or Code 107) Tantalum
C10 ……………………….5pF (or 4.7 pF) ceramic-high quality
C11………………………. 2.2uF-16v (or Code 225) Tantalum
C13, C17, C25 ……………………….470uF-16v electrolytic
C15, C16 ……………………….4700uF-16v electrolytic
C19, C22 ……………………….1000uF-16v electrolytic
C24 ……………………….2200uF-25v electrolytic
* Ceramic capacitors voltage isn’t important.
*you can Use a capacitor with higher voltage but don’t use capacitors with lower
voltage at all.

Resistors

——————————————————————————————-
R1, R17, R21 ……………………….1K
R2, R16 ……………………….47 ohm
R3 ……………………….10K
R4, R14, R20 ……………………….4.7K
R5, R18………………………. 2.2K
R6, R15………………………. 10 ohm
R7 ……………………….1.5K
R8 ……………………….1.8K
R9 ……………………….1M (one mega-ohms)
R10………………………. 100 ohm
R11, R12 ……………………….390 ohm – 2W
R13………………………. 18K
R19………………………. 22K
* All 0.25w1% carbon film except R11 and R12 (these are 2w and 1% metal film
or better)

Transistors

———————————————————————————————–
T1…………………… BS170 original
T2 ……. .…………….IRF840 or STW11NK100Z (MOSFET)
T3 ……………………BC337

Iintegrated Circuits

———————————————————————————————–
U1……………. ATmega328P-PU (microcontroller) Type 28 pin
U2……………. . LF357N, not fake (LF357H metal, LF157, LF257)
U3……………. . L7805CV, high quality of 5V regulator
U4……………. . L7812CV12 volts 1.5 A, high-quality regulator + small and strong

Other parts

———————————————————————————————–
X………… 20MHz crystal 20 MHz (20.000 or 20.0000 or 20.000000)
D1, D2 ……………………………….1N4148 diode
D3 ……………………………………1N5819 diode
LCD……………………………… 16*2 character LCD with backlit
SP……………………………… small 8 ohm speaker, 0.2 W or more piezoelectric speaker
or headphones.
BAT……………………………………. . Battery 18 to 24 V, 2-4 amps
LOOP…………………………………. . 350uH – 1 ohm – Spider-loop search (proposed)
S ………………………………. .5 high quality push button mounted box (normal cut and pressed mode Contact)
PCB……………………………… 7.3 x 7.9 cm fiber – rather than fiberglass

FelezJoo PI assembly

If you have done the exact PCB and prepared the necessary parts, you can start building your FelezJoo PI by putting parts from smallest to biggest

FelezJoo PI System settings

For enter in Felezjoo menu, press OK to enter in the System settings. Using the up and down keys, you can switch between options. And using the left and right keys, you can change the desired options.

Frequency : Range= 35 to 999Hz:

This setting determines the frequency pulse is the pulse detector. Those who have worked with a variety of policy, are familiar with this concept, and therefore do not need much explanation. Lower frequencies penetrate the soil more and less susceptible to soil type, but smaller and less sensitive to metals also quickly sense and are less explored. If the high frequencies are reversed. At the same time power consumption also increases with increasing frequency. It is recommended to use frequencies between 200 and 300 Hz, to get good answers for different situations.

Pulse Width:(100-500)

This setting is based on the concept of microseconds pulse width transmitter and the signal strength directly involved. In fact, the setting of the tuning frequency of the regulation, which determine the conditions of pulse transmitter and digital pulse detector circuit is almost not the same, by setting the pulse width, it can be certain of the loop, even with the large size, and even better conditions than Ohm and capacity pulse power loop and soil type, adjusted. A total of achieving the desired result in this case, need to experience. More pulse width means a higher current in the loop as well, but the high current loops may be smaller and smaller targets, is problematic. For example, small amounts of gold, with a high pulse width, almost no sense, if the goals of the larger, more pulse width, the better answer.

Delay

This setting is related to the client device determines that the calculations sense of patrimony wave back, after how much time, in microseconds, after the end of the pulse to be done. First, I note that this device has a unique method called Delay Finder software that can balance during the fraction of a second to find the Daily loop start, set the Delay left hand menu, in actually means that, starting from the moment of automatic Delay is equivalent to the amount of 0, we have much excess Delay in microseconds. After the number is set, it actually means for the Daily Additional Delay is in addition to that amount. This setting is important because, metals like gold, small, practically requires Delay less good sense, but in this case, metal detectors, are more susceptible to the effects of land and minerals will, then it is possible to soil type, better Delay lowered manually.

Integ.W: (Integration interval)

This setting, which is a unique and professional settings compared to other existing schemes is the fact that, in practice, the integration criterion metal sense, that is the return signal, what period in microseconds after Delay continues.
In some analogue circuits such as the RX Width Set is called. The exact range of integration, from the moment of automatic Delay + also manually Delay start, and the size of the set value for this setting, continues. If Delay is set manually on the 10+, and Automatic Delay loop 15 will be announced, and adjust Integ.W on the 30, the 25 to 55 microseconds integral calculation, after the pulse transmitter will be done. Delay adjusts this setting, in the sense with various metals, and sensitivity to certain minerals, as well as the influence of ambient noise is effective. It should be noted, reduce the excessive amount of regulation, leading to the loss of a large range, and as it may seem, however, to take a little more metal detectors, but at the same time, the possibility of the sensitivity of some minerals, as well as unaffected by the noise also increases.

Ground: (automatically adapt to the ground)

This setting, which is a unique and professional settings compared to other existing schemes is the fact that, in practice, the integration criterion metal sense, that is the return signal, what period in microseconds after Delay continues.
This setting is similar with SAT (Self Adjusting Threshold), the advanced pulse detector, which has the potential improvements over the standard, more like a feature Tracking, GPX minelab series devices operate. This setting is very important during long searches, makes it a simple metal detector is with respect to many projects, and the operator when the search is much easier, because it eliminates the need to balance succession, so that if Explore the sudden change does not happen, or the device itself be hours, unlike most circuits, the metal detector will still remain in the set up mode. Enable this setting also makes the device itself permanently, by changing weather conditions, which affect the stability of the circuit is synchronized, and always with the same sensibility that set, he expected to Metal Detecting offer. OFF value means that this feature is disabled, and then repeated the need for balance in the exploration, there will be, instead, be a little more sensitive offers. This feature is enabled other values means. Lower numbers, symbols automatically adapt faster and higher levels, adapting means slower and longer.

Speed: (accelerate to sensing)

This setting is similar to feature in Motion series GPX Minelab metal detectors intended, and actually determines the speed of sense, or reaction with respect to the metal. The metal detector did not function in normal programs, causes stability and noise, as there is very good, and while exploring additional horns have much lower. Lower values mean less speed and maximum stability of sense and antisense noise and higher values mean more speed, which is less stable and therefore there will be more noise. Selection of this arrangement, the operator quickly and naturally explored to some extent, depends a great loop, and to achieve greater stability However, if needed, to sense the speed set on the lower level. Naturally, the lower the need for slower speed loop, there is the possibility of losing goals or less, there will be. In fact, set a lower value for the option, at the same time can automatically; eliminating the possibility of more small targets, and provides particles.

Iron Reject: (iron removal)

This setting is similar to the GPX Minelab series , And by a complex formula of iron diagnosis, is done. OFF value means the ability to remove iron is disabled, and the values of 1 to 30 also enable this feature, specify the degree of iron removal. Whatever the number, the higher the setting, making removal more difficult and can even lead to the removal of other metals. If this setting is enabled, and the sense of iron is detected, the audio output will be cut off, but the graphs and meters as well as number sense and resolution, LCD screen will continue to show the objective sense. Working with this parameter and calibration of the device, according to the conditions of manufacture, and loop environment to explore, with important points that will be described below. Set this parameter for each loop is different, and should be in the right condition for the different loops and away from metal annoying, tested and see what degree, the iron removal loops do so for the same loop, set the same degree, Note that higher and put this parameter can be the result of confusion, and the elimination of non-ferrous materials as lead, after testing must be accurate and consistent, this parameter set.

Backlight

This setting adjusts the degree of light LCD with digital, the value OFF means light off, and 10 is the maximum light from the LCD screen. It should be noted that some types of LCD, with different lighting systems, in which case you need to manipulate the jumpers behind the LCD screen, so light does not work properly. In this case, if the jumpers are not changed, the LCD should be used with other brands. It should be mentioned, the LCD light on the circuit is designed in such a way that, even in maximum light, power consumption will increase, and so the idea was not to worry.

Contrast

This setting is very similar to the previous setting, but to control the amount of black on the LCD's contrast or intended. The figure below highlight means of
posts, and more data means more light is being written. Considering the differences between LCD and also, with the point of view of the operator of the LCD screen to position LCD on the box, and the structure of the device depends on the operator would adjust so do, which is written in the best bit, the eye be the operator.

Volume

This set of audio output power circuit OFF means that the sound is cut off completely, and 10 means maximum power of sound. The plan also audio system, an incremental mode is intended for voice, thus when metal comes closer loop, the sound is a little stronger. For more efficient use of this mode, it is recommended to set the sound volume on the lower levels. If the volume level is greater than 7, the operation will not significantly affect the volume.

Tones

This regulation is concerned, the sound output mode to respond to sense the metal. The values 1, 2 and 3 each monologue in the voice, or bass, or bass levels 4, 5 and 6 are two sound and the amount of 7 three sound. But the 8 is as 3 sounds and depending on the proximity to metal and power sense, works. This means that when a weaker sense, the voice is falsetto, and the closer to the metal's voice becomes stronger, where more bass, and finally when he is sensing metal strongest, most bass the sound is produced. The sound is strong goals help to identify more precisely the center. Ingredients that prioritize voice and bass voices, more precise and safer for the sense intended purpose has helped to true and false targets or random noise should be recognized. The choice depends on the tastes of the operator's voice, but it is recommended to use combinations of voices. While in some cases 4, 5 and 6-speed voice, the voices modulate naturally depends on the operating frequency metal detector, but the monologue, as well as three 8 mode, there is no association between the frequency of the metal detector and sound.

Doanload files

Sprint-Layout 6.0

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