felezjoo PI(the best pulse induction metal detector that I made until now)

[useus]

I built a small spider coil to look for mostly gold.
the coil has the following characteristics


27 turns 0.45 copper wire
inner diameter 65mm
outside diameter 120mm approx
4.5 ohm
autodelay 14
good A B C values 296-703-798 (improved by modifying pulse)
I have not yet measured the inductance but it is almost certainly about 400uH
since the coil came to me decently, before removing the turns I ask you.


Is autodelay 14 a good value for gold research or is it necessary to approach the autodelay 20 value as recommended in the various guides?


thanks

[Qiaozhi]

Comprei o integrado lf 357 4 vezes aqui no Brasil! e tudo falso!

N?o sei que dispositivo montar aqui no sul do Brasil ... terras altamente mineralizadas ... nem projeto d? certo!

Please post in English.

[folharin]

N?o sei que dispositivo montar aqui no sul do Brasil ... terras altamente mineralizadas ... nem projeto d? certo!

[folharin]

I managed to make it work by exchanging the 390 homs resistor for a potentiometer..but it wasn?t functional for a long period..very unstable

[folharin]

Comprei o integrado lf 357 4 vezes aqui no Brasil! e tudo falso!

[mohamadreza26204]

full felezjoo schematic

https://uupload.ir/files/42e6_index.jpg

https://uupload.ir/filelink/kSVJtwFkyS7W/y39y_%D8%A6%D8%A6%D8%A6%D8%A6%D8%A6%D8%A6%D8%A6%D8 %A6%D8%A6%D8%A6%D8%A6%D8%A6%D8%A6%D8%A6%D8%A6%D8%A6%D8%A6.pdf

https://uupload.ir/filelink/wstk2D5AXMVS/bwk9_%D8%A6%D8%A6%D8%A6%D8%A6%D8%A6%D8%A6%D8%A6%D8%A6%D8%A6%D8%A6%D8%A6%D8%A6%D8%A6%D8%A6%D8%A6%D8%A6%D8%A6.pdf

[mohamadreza26204]

[sbalio1]

You can use TL061 instead ca3130 or ca3140

[ionut_mtb]

-coil must be spider for best result and correct ABC numbers
-have to use propper coaxial cable for coil connection
-use piezo speaker

[ionut_mtb]

Hello

I just finished the detector !

I used Felezjoo PI TYPON 2.zip to make the pcb with jclpcb, I had 2 problems, on the pcb the resistance at the top is wrong, on the pcb it is indicated 10k but on the diagram it takes a 2.2k .
i used a 2.2k it works.
the second problem is the size of the capacitor, 4700, 2200 and 1000uf are too big for the pcb, maybe I will have used 35V instead of taking 50V ....


I confirm that the "CA3130EZ" perfectly replaces the LF357

I now have a small problem, the L7812CV is heating up, did you use a radiator on this regulator?
the circuit is supplied with 24V
at start-up: 45mA
with coil: 130mA
with the coil and in detection: 140-150mA
with only 150mA the regulator is burning .....


I am now looking for information on the manufacture of "spider coil"....
do you have any links to advise me?

with a coil of 7cm, 1ohms, 0.357mH I get A559 B814 C826

a big thank you to the forum
[ATTACH]54980[/ATTACH]

-voltage regulator must have heatsink
-you have to use correct components, looking at your board i don’t see tantalum and ceramic capacitors.
-current should be ok, depend on the coil and pulse width.
-number A is high, maybe because of CA3130
-24v i think is quite high

[windaube]

Hello

I just finished the detector !

I used Felezjoo PI TYPON 2.zip to make the pcb with jclpcb, I had 2 problems, on the pcb the resistance at the top is wrong, on the pcb it is indicated 10k but on the diagram it takes a 2.2k .
i used a 2.2k it works.
the second problem is the size of the capacitor, 4700, 2200 and 1000uf are too big for the pcb, maybe I will have used 35V instead of taking 50V ....


I confirm that the "CA3130EZ" perfectly replaces the LF357

I now have a small problem, the L7812CV is heating up, did you use a radiator on this regulator?
the circuit is supplied with 24V
at start-up: 45mA
with coil: 130mA
with the coil and in detection: 140-150mA
with only 150mA the regulator is burning .....


I am now looking for information on the manufacture of "spider coil"....
do you have any links to advise me?

with a coil of 7cm, 1ohms, 0.357mH I get A559 B814 C826

a big thank you to the forum

[ricalbertvig]

that is a better path to go
now after trying a few times it seems like I can't find the right data format to apply changes and then the checksums
this is the online editor:
[ATTACH]54835[/ATTACH]
does not seem right
if this is the right format the 8th pocket should be checksum but it does not correspond to that
I tried HxD editor and didn't even get the ascii on the right side

I have tried but when I save or expert the edited hex I get the result of the saved .hex .. but the .hex is different from the original I don't know why ..

[Mr.Jaick]

You don't want to modify the EEPROM contents, but the .hex file and after modification program it back to the controller.
You can edit the hex file with a hex editor or online with eg https://hexed.it/

Then find the string you want to modify and save as eg "felezjoo_mod.hex".

that is a better path to go
now after trying a few times it seems like I can't find the right data format to apply changes and then the checksums
this is the online editor:

does not seem right
if this is the right format the 8th pocket should be checksum but it does not correspond to that
I tried HxD editor and didn't even get the ascii on the right side

[Semih BULGUR]

Iron Rejection or iron removal is great idea! It is priceless tip for hunting rare metals. l learnt very important informations from this forum. Thank you indeed!

[ricalbertvig]

Hello, good morning everyone, has anyone been able to eliminate the 3.35 counter? since in tests I have realized that it is more stable than full 3.35 .. greetings