Arduino Nano PI Main Discussion

[surfdetector]

Hi Carl: And using it underwater with a waterproof coil, since the salinity is similar everywhere, will that effect occur?

The salinity when constantly submerged in the salt water is uniform as opposed to swinging in and then out of the surf.

[ionut_mtb]

What is the size of the pcb?

[Qiaozhi]

What is the size of the pcb?

3.25" x 3.00" (82.6mm x 76.2mm)

[mermelado]

The salinity when constantly submerged in the salt water is uniform as opposed to swinging in and then out of the surf.

Then would it be correct to say that a PI detector is more stable under the sea than outside of it? and by the way, does anyone have any links to build submersible coils and types of submersible cables for them?

[jhughes1010]

Just got the book and typing in the sketch. The ISR seems to be missing a line of code above the switch statement, but not 100% certain. I just see a bracket pairing mismatch. Anyone have any ideas? Is there a repository that contains the code? Not against typing it in, but do not want it to be harder than it should be.

[Agme]

https://www.geotech1.com/forums/show...hed-March-2021

this link is the thread with all the files.

This thread is for questions and discussions the info you are looking for is in the technical papers and books section.

[Qiaozhi]

Just got the book and typing in the sketch. The ISR seems to be missing a line of code above the switch statement, but not 100% certain. I just see a bracket pairing mismatch. Anyone have any ideas? Is there a repository that contains the code? Not against typing it in, but do not want it to be harder than it should be.

Everything you need is here -> Arduino Nano Pulse Induction Metal Detector Project - Published March 2021

It appears that you have spotted an error at the top of page 23. The missing line is "ISR(TIMER1_OVF_vect) {".
I'll create an errata in the above link.

[jhughes1010]

Thanks for pointing me in the right direction on the design collateral!

[Rzouga]

Hi George and all members!
I just received yesterday the two books: Arduino nano PI metal detector project, and The Voodoo project. What an exciting journey is waiting for me after some years away from electronics!!
Thank you for sharing this knowledge!

[Carl-NC]

Hi Carl: And using it underwater with a waterproof coil, since the salinity is similar everywhere, will that effect occur?

In calm water, no. But if there are waves then the volume of water above the coil will vary and you might hear this.

[mermelado]

[QUOTE = Carl-NC; 290544] En aguas tranquilas, no. Pero si hay olas, el volumen de agua sobre la bobina variar? y es posible que escuche esto. [/ QUOTE]

Thanks Carl

[Rzouga]

Hi experts,
I finished reading the book, ordered my PCB, and about to order the missing components. However I have 3 questions:
1-I cant find the darlington MPSA13, and found out that a BC516 can replace it with no issues. Can somebody please confirm or went through the same issue?
2-Is it mandatory to have Sample delay and Threshold pots as multiturns or normal pots would work fine?
3- I am thinking of powering up the detector from a 12v powerbank instead of building the charger (as an easy and more practical way) did anyone try this before?

[surfdetector]

Hi experts,
I finished reading the book, ordered my PCB, and about to order the missing components. However I have 3 questions:
1-I cant find the darlington MPSA13, and found out that a BC516 can replace it with no issues. Can somebody please confirm or went through the same issue?
2-Is it mandatory to have Sample delay and Threshold pots as multiturns or normal pots would work fine?
3- I am thinking of powering up the detector from a 12v powerbank instead of building the charger (as an easy and more practical way) did anyone try this before?

• BC516 is a PNP Darlington, The MPSA13 is an NPN
• The sample Delay and Threshold are normal single turn pots
• You can certainly power from a 12V pack, the charging circuit is not necessary

I did a video set on the Arduino Nano build here, you might find it helpful:
https://youtube.com/playlist?list=PL...vygh0x9WRf4jag

[Rzouga]

• BC516 is a PNP Darlington, The MPSA13 is an NPN
• The sample Delay and Threshold are normal single turn pots
• You can certainly power from a 12V pack, the charging circuit is not necessary

I did a video set on the Arduino Nano build here, you might find it helpful:
https://youtube.com/playlist?list=PL...vygh0x9WRf4jag

Hi surfdetector,
Thank you for the quick answer
My bad, that was my mistake I meant bc517 which is also an NPN darlington, It is a bit difficult to find an equivalent to the MPSA13, if you know any please be my guest.

I have to say that I knew about the book and about this forum thanks to you and your videos (I think I watched the 4 of them more than 3 times or so )

[MartyJ1963]

I have used:- MPSA14, MPSA12, 2SC982, 2N6426, MPSW45, ECG46, 2SC982, 2N5525, 2N5306, 2N6427, 2SC1472, BC517, 2N7051, 2N7051 in place of the MPSA13 on other detectors with no issues. Also, I power my ANPI's with 3 x 18650 batteries and just replace the batteries when they delete,,,they last me about 8 hours or so. Regards, Marty.