Arduino Nano PI Main Discussion

[Qiaozhi]

Hi Qiaozhi,

My book arrived last night great job again.
I was trying to run verify and compile and having problems, but I was trying to compile to a galileo gen 2.

If I switch to the nano board it compiles fine.

Thanks.
Yes, you have to remember to set the target system under Tools > Board.

I was wondering if you had to do anything different to the code for the R3 you first tried?

The sketch will compile for both Nano and Uno without any modifications.

Also looking at the schematic could U4-3 be replaced with a J113 freeing up the 4066 to add two more sample pulses?

I think that should work OK.

I really like this platform if we add a simple sd card we can boot different detector sketches having multiple machines available.(salt program, deep hole, relic, prospecting machines all in one).

A few tweaks to the board, Mur 460 dual pre amp, gain pot at Ic3a maybe would be needed of coarse.
Or even just use the SD for checking many different settings in the field and not having to connect to the Arduino.

Thanks again .

As I replied in a previous post, the diode and dual-stage preamp were not included in this design, because I used Surf-PI as a basic core, and these modifications are not really useful for a beach detector. Also, I wanted to keep the design reasonably simple for people who are coming from an Arduino rather than electronics background.

I agree though ... this platform provides a really good basis from which to try out many different ideas. The Nano gives it great flexibility with the advantage that the IDE is open-source. If anyone wanting to expand on this design could also use DipTrace for schematics and PCB layout, that would allow more people to become involved. The free version of DipTrace is limited to 300 pins, and this design used 210. You can also upgrade to a 500 pin version for only $145, and there are 1000, 2000, and unlimited versions beyond that.

[Qiaozhi]

OK. I didn't see any error in the text. Excellent job George and Andy. Also the drawings are clearer than in the Vodoo project book.

Yes, I learned a lesson from publishing the Voodoo Project where I tried to avoid redrawing the schematics and hence create additional errors. However, it only introduced a different problem. So this time I carefully redrew everything using Inkscape, which has similar capabilities to Visio, but is free.

Only one question George. Why didn' you include the improvements of the 2 stage preamplifier, and the serial diode in the TX swich as you did in the MPP project?

It could be for future improvements?

Regards to all in the forum

Phantom

The Arduino Nano PI project is designed for the beach, as its basic core is the Surf-PI. Therefore it was not necessary to include either the series diode or a dual-stage preamp. In fact this design can go as low as 10us for the main sample delay, which is probably a bit too low for wet sand.

[godigit1]

Hi Qiaozhi,

My book arrived last night great job again.
I was trying to run verify and compile and having problems, but I was trying to compile to a galileo gen 2.

If I switch to the nano board it compiles fine.
I was wondering if you had to do anything different to the code for the R3 you first tried?

Also looking at the schematic could U4-3 be replaced with a J113 freeing up the 4066 to add two more sample pulses?

I really like this platform if we add a simple sd card we can boot different detector sketches having multiple machines available.(salt program, deep hole, relic, prospecting machines all in one).

A few tweaks to the board, Mur 460 dual pre amp, gain pot at Ic3a maybe would be needed of coarse.
Or even just use the SD for checking many different settings in the field and not having to connect to the Arduino.

Thanks again .

[Phantom]

I thought you may have found an error, but in fact that is correct.

The syncDemodOn state needs to be LOW in order for the input to the sample gate to be HIGH. That's because the signal goes through a voltage converter circuit which inverts the state. The same applies to syncDemodOff. See Fig. 2-1.

If it had been an error, I was going to blame Andy's proofreading.

OK. I didn't see any error in the text. Excellent job George and Andy. Also the drawings are clearer than in the Vodoo project book.

Only one question George. Why didn' you include the improvements of the 2 stage preamplifier, and the serial diode in the TX swich as you did in the MPP project?

It could be for future improvements?

Regards to all in the forum

Phantom

[Qiaozhi]

if i get asked for my favourite author of modern literature i can say : oh i got a unique collection of electronic books from G.O.

btw. did silverdog made a testvideo, would like to hear detection sound

It sounds like a Surf-PI. The audio tone is 490Hz which varies in volume depending on the strength of the target signal. You can adjust the threshold control to either be silent search or to provide a faint background tone. The latter is preferable if you're looking for small or deep faint targets.

[bernte_one]

if i get asked for my favourite author of modern literature i can say : oh i got a unique collection of electronic books from G.O.

btw. did silverdog made a testvideo, would like to hear detection sound

[Qiaozhi]

George: In your opinion, what are the pros and cons of this detector vs the Voodoo project?

The Arduino Nano project is based on the Surf-PI. The Nano provides the +5V supply to the rest of the circuitry, the TX oscillator signal, and all the sample timing. It also generates the audio tone. In the original Surf-PI the audio tone is dependent on the TX pulse rate, but this dependency is removed by the Nano. An additional feature is the Boost switch that changes the TX pulse width from 50us (normal) to 100us (boost). Advantages of this design are that all the design data is open-source. The Arduino sketch is readily modified using the IDE, and the schematic and PCB files can be viewed and modified in DipTrace. Both the Arduino IDE and DipTrace are free.

Voodoo is a more advanced project which provides ferrous rejection that is not based on target conductivity. The disadvantage for the hobbyist is that the software was developed using mikroElektronika's mikroC Pro platform, and the schematic and layout were designed using EasyPC. Neither of these packages are free.

It really depends on your perspective as to the pros and cons. Clearly the Arduino Nano detects all metals, and is therefore intended for beach use, whereas Voodoo can also be used inland where other pulse induction designs are not suitable.

[wallaby]

George: In your opinion, what are the pros and cons of this detector vs the Voodoo project?

[Qiaozhi]

another thread seems good : https://hack-review.com/software/ard...ctor-by-jorbi/

Interesting ... I've not seen that link before.
Although the Arduino code is actually for a BFO design, even though he talks a lot about PI in the main text.

All the Arduino-based PI designs I've seen do not include an EFE sample. They also directly sample the preamp output, and with the Arduino's 10-bit ADC resolution they exhibit poor depth.

[AK48]

another thread seems good : https://hack-review.com/software/ard...ctor-by-jorbi/

[surfdetector]

I thought you may have found an error, but in fact that is correct.

The syncDemodOn state needs to be LOW in order for the input to the sample gate to be HIGH. That's because the signal goes through a voltage converter circuit which inverts the state. The same applies to syncDemodOff. See Fig. 2-1.

If it had been an error, I was going to blame Andy's proofreading.

Thanks for the explanation, I was scratching my head.

[Qiaozhi]

George,
In reading through the Sketch I have a question about the following line on page 18.

const byte syncDemodOn = LOW; // Sample gate turns on when input high

Should the description not be, // Sample gate turns on when input is low

I thought you may have found an error, but in fact that is correct.

The syncDemodOn state needs to be LOW in order for the input to the sample gate to be HIGH. That's because the signal goes through a voltage converter circuit which inverts the state. The same applies to syncDemodOff. See Fig. 2-1.

If it had been an error, I was going to blame Andy's proofreading.

[surfdetector]

George,
In reading through the Sketch I have a question about the following line on page 18.

const byte syncDemodOn = LOW; // Sample gate turns on when input high

Should the description not be, // Sample gate turns on when input is low

[Qiaozhi]

Very funny!

I've tried twice (on different days) on the first post link and Amazon.co.uk was saying "OUT OF STOCK" (anyway sometimes has happened to my KDP book too).
Now everything is OK and I've bought my copy!

Great job George!

Regards,
Leonardo

[Bodhi3]

Very funny!

I've tried twice (on different days) on the first post link and Amazon.co.uk was saying "OUT OF STOCK" (anyway sometimes has happened to my KDP book too).
Now everything is OK and I've bought my copy!

Great job George!

Regards,
Leonardo