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

[liudengyuan]

This is a restricted hex, detect a stability is far from xr 71 didn't good, the best circuit is xr 71,

[koohyar]

[QUOTE=ossman22;206679]

If you have built this detector,

Technical issue ( Iron Rejection option )

I don't understand Farsi language well but have read several pages on Iranian forum and found out that Discrimination or better to say iron rejection option, beside other issues, highly depends on some components quality factors or better to say components details factors

For example iron rejection works just with some kinds of LF357 op-amp not all LF357 just a few of them and must consider suffix and special part numbers on LF357

Iron rejection does NOT work with any LF357.

Other component is irf840. It is also like lf357 and not any type of irf840 let to have iron rejection and must use special parts with exact part numbers that mentioned on Iranian forum

Also cable used for loop making and its connection also its connector must be considered and obtain special type

So, it is very hard to have correct iron rejection in felezjoo pi

Without iron rejection no problem to use what kind and quality of materials

Anyway, I appreciate designer work and efforts and thank you ( specially its designer named Hamid ) for sharing information.

hi
tnx for the informations.
However, It is important to add that,
For that you get the best out of the iron removal,
Just be careful, use of parts that are original.
Pieces such as LF357 and IRF840 or 11NK100 and BS170 must be original and not counterfeit.
Then for approval of parts just check three separate channel numbers, which are close to these numbers. (300, 700, 800)
designer, very recommends to use of original parts,
But really, why?
Unfortunately in Iran, Due to international prohibition Most electronic parts imported from China and this has led, many fake parts, to enter the market.
But surely you will not have any problem in providing original parts.

[Qiaozhi]

sorry for text direction ( posted English right to left). always have this problem using bilingual windows. sorry for inconvenience.

Thanks for posting that information.
It's more or less as I suspected.

[ossman22]

sorry for text direction ( posted English right to left). always have this problem using bilingual windows. sorry for inconvenience.

[ossman22]

[QUOTE=Qiaozhi;206555]If you have built this detector,

can you please tell us how well it rejects iron? Can it do this for different sizes and different shapes?

Technical issue ( Iron Rejection option )

I don't understand Farsi language well but have read several pages on Iranian forum and found out that Discrimination or better to say iron rejection option, beside other issues, highly depends on some components quality factors or better to say components details factors

For example iron rejection works just with some kinds of LF357 op-amp not all LF357 just a few of them and must consider suffix and special part numbers on LF357

Iron rejection does NOT work with any LF357.

Other component is irf840. It is also like lf357 and not any type of irf840 let to have iron rejection and must use special parts with exact part numbers that mentioned on Iranian forum

Also cable used for loop making and its connection also its connector must be considered and obtain special type

So, it is very hard to have correct iron rejection in felezjoo pi

Without iron rejection no problem to use what kind and quality of materials

Anyway, I appreciate designer work and efforts and thank you ( specially its designer named Hamid ) for sharing information.

[Wiltran]

How is this detector substantially different than Stuart microcontroller pulse inductor detector? Microcontroller controls timing, pulse etc. Being a pulse induction system, how does it accurately perform VDI? Has anybody actually built this?

[koohyar]

Password means you can set a password (numbers) to make device private.Then when device starts again, it asks password to run. This option (password) provided to NOT allow non-owner use device without your permission.Here is a kind of anti-theft option

tnx

[ossman22]

Password means you can set a password (numbers) to make device private.Then when device starts again, it asks password to run. This option (password) provided to NOT allow non-owner use device without your permission.Here is a kind of anti-theft option

[pluto923]

This is a picture of programmer you see option password



http://www.geotech1.com/forums/newat...manager&values[p]=206643&editpost=1&contenttypeid=1&poststarttime=1 438148738&posthash=b6d7c3ba691038eb81abd9c99b8e753 5&insertinline=1

[mrmr16]

dear kohyar

thank you for create this Topic

this project in Iranian site have 1167 page and 11670 post

everybody that want to build it must have accuracy


I thank Mr. Hamid from Iran for this powerful and simple project that is provided free of charge to everyone.

I love Iran and Iranians

https://www.felezjoo.com/viewtopic.php?f=8&t=2182

[pluto923]

Hi Nick, thanks for the finished file as TYPON 2. Do you have any information about password-felezjoo pi.hex

[sinclairuser]

hi all well done for this new project, i can manage everything else for this build but the chip.
is anyone in the uk or euroland interested in selling me a programmed chip or two.
pic's and coolrunners i can do but i have no way to program these chips.

to be honest this project has enough infomation and support for someone to do some kits

thanks,
aly.

[6666]

Unlike bipolar transistors (which are current-driven), MOSFETs are voltage-driven. From the IRF840 datasheet you can readily see that Vgs threshold is 4V (max), which means that it needs to have at least 4V to turn on (and preferably much higher) up to the maximum rating of 20V. From the datasheet graphs, it is clear that Id plateaus at about Vgs=8V. This means that the resistor value of 2k2 is perfectly ok, as this will apply 12V to the gate. MOSFETs have a very high input impedance, and (from the datasheet) it is possible to calculate this value for the IRF840 as being 200M (from Vgs=20V and Igss=+/-100nA). So there is no need to be concerned about gate current. In fact, a value of 10k would work just as well as 2k2.

Hi Qiaozhi
Thanks for your reply, since your reply I've had a quick look at the data sheet, I've always had the impression that to turn on a power fet hard the power fet needed the full gate voltage fed by a low resistance path so the gate could draw as much current as required for full turn on , and hence I've favoured and used ccts similar to Eric's that use a transistor to dump the full supply voltage onto the gate.
The Atmega328p chip arrived, but I'm down with a cold virus right now and my brain is mush, so will return to this in few days.

[WM6]

you must have a good magnifier !!!!!

Eyeglasses diopter +2.5.
Regarding LAY file you posted, coil data need to be corrected: not 350uF but 350uH.

[nick holas]

thanks too for your help Qiaozhi for your help!!!