Spirit pi 4 Pro metal detector by Neco Desarrollo

[gbrowne]

Hi,

I was wondering if anyone else had discovered this PI design by Neco Desarollo. https://neco-desarrollo.es/wp-conten...-corregido.zip
Arduino-nano based, it uses a couple of NE5532 op-amps for signal processing and the usual pulse driver circuitry.

He has published the source code and also the schematic (and even GERBERS!) but there is very little in terms of circuit desciption. Most of it seems fairly straightforward however.
There are various youtube guides on how to assemble etc.. https://www.youtube.com/watch?v=0ejwu_3nQ6M for one.

I just wondered if anyone had discovered it and if they'd had a go ? I've breadboarded it, but not quite got it going yet.

Cheers,
Geoff.

[Qiaozhi]

Hi,

I was wondering if anyone else had discovered this PI design by Neco Desarollo. https://neco-desarrollo.es/wp-conten...-corregido.zip
Arduino-nano based, it uses a couple of NE5532 op-amps for signal processing and the usual pulse driver circuitry.

He has published the source code and also the schematic (and even GERBERS!) but there is very little in terms of circuit desciption. Most of it seems fairly straightforward however.
There are various youtube guides on how to assemble etc.. https://www.youtube.com/watch?v=0ejwu_3nQ6M for one.

I just wondered if anyone had discovered it and if they'd had a go ? I've breadboarded it, but not quite got it going yet.

Cheers,
Geoff.

There are a few of these Arduino PI metal detector designs to be found on the internet, but they tend to vary in quality somewhat.

Neco seems to be doing some interesting stuff in his videos, although I wish his schematics weren't so obfuscated, and that there were a lot more comments in the code to assist in understanding what's going on.

The Spirit PI uses a single-stage preamp with a huge amount of gain, followed by a sample gate and two further amplifying stages before going to the Ardunio A0 input. There doesn't appear to be any integrator stages, and the audio is generated on D10 using the Arduino Tone library.

I presume you've seen the Arduino Nano PI detector project here? -> https://www.geotech1.com/forums/show...hed-March-2021

[gbrowne]

Hi George, Thank you for the quick reply. Sadly, I hadn't discovered your excellent Arduino project, which looks very interesting and WAYYY better documented and explained than what I've been struggling with!
I will read through the thread and learn. The videos are really helpful.
Do you get similar reasults to the Surf-PI as seen here https://www.youtube.com/watch?v=7M5RpMLhRrs ?

Geoff.

[Qiaozhi]

Hi George, Thank you for the quick reply. Sadly, I hadn't discovered your excellent Arduino project, which looks very interesting and WAYYY better documented and explained than what I've been struggling with!
I will read through the thread and learn. The videos are really helpful.
Do you get similar reasults to the Surf-PI as seen here https://www.youtube.com/watch?v=7M5RpMLhRrs ?

Geoff.

See this post -> https://www.geotech1.com/forums/show...948#post286948

In the video link you posted, the detector shown there is not a standard Surf-PI circuit, and whatever changes have been made are not in the public domain. Also, the audio has been changed to a VCO-type output, which many people find annoying. The standard Surf-PI, and the Arduino Nano PI detector, both have a fixed audio tone that increases in volume with the strength of the target signal.

[Leonce]

I have build this neco spririt pi, the LCD version. I am struggling to make it work. It seems that it is not as stright forward as it presumes. I have double checked all components several times. I even built another one from scratch. It looks like some resistors have critical values that have to be found using an oscilloscope in order to fin which value triggers the ne5534.