PICKINI V3 - an easy to build PI detector

[F117]

Since this is a major modification of PICKINI V1/2 http://www.geotech1.com/forums/showt...etector/page13
maybe it's better to start a new thread.

After having built quite a few of the V1 and V2 PICKINI detectors, it was time for some changes:

V3 is largely based on the same principle = flyback pulse width measurement.
This principle is described in the book "Inside the metal detector" on page 170 = PI design 5.

Major differences from V1/2:

• smaller single sided PCB footprint: [35 x 110 mm] or [1.38 x 4.33 inch] fits nicely in a drain tube.
• simpler power supply: unregulated 10V - 14V DC, so less batteries needed.
• new analog frontend around NE5532 opamp + virtual ground - as described in ITMD.
• smaller microcontroller: 8 pin PIC 12F1840.
• new mechanical design: straight stem from crutch, coil shell and lower stem were bought.
• optional pinpoint pushbutton: switches the detector into non-motion, allowing it to hover over the target
• extra audio signal when no flyback is detected = "coil error sound" - mostly caused by bad coil connection.

The entire description and download section can be found here:
http://users.telenet.be/willaert/MD/.../V3/intro.html

pickini_v3_beach_1.JPG

[6666]

Well done, thanks.

[F117]

Detail of the PP (non-motion) pushbutton embedded in the handle bar.
Swing in motion mode until a target is detected. Keep the coil away from the target and push the pinpoint button.
Hover over the target and a continuous signal will indicate the exact target location:




Have fun,
- Bernard

[F117]

Well done, thanks.

thank You 6666.
Something simple, yet powerfull to keep you going trough the summer
It took me most of winter and spring to debug / test / develop... everything.
There was at least one major bug in the code of the V2 software, around the sensitivity potmeter readout.
I did extensive field tests with it before discovering that if you turned the potmeter very slowly (or even normal slowly) that the value was not updated.
Only when you cranked it up in one turn to max sensitivity it would accept the new value.
This is also why I won't publish source code anymore, only the hex file. I now have it debugged and tested properly and everything works as planned.
The basic source code is identical to V2, but with another processor and bug fixing. It was just another proof to me how long it takes to design, develop, field test and publish a simple piece of SW/HW combination as this PI detector (single handedly).

Best regards,
- Bernard

[edu38]

Hi:
is posible to replace the 12f1840 (unavailable in my country) with 12f675 or other pic with the same code? Thx in advance ,congratulations to the developèrs,,,,,Eduardo from Bs. As

[F117]

Sorry, Eduardo, but I will not port the code to any other flavours of Microchip. I have done this in the past and although, they are all "alike" and pin compatible, there are some sneaky little differences in the internal resources and even differences in code.
There seem to be quite some Microchip distributors in Brasil and the 12F1840 is relatively new and widespread, so it should be possible to get some samples:
http://www.microchip.com/distributor...SA&terr=Brazil

Good luck,
- Bernard

[bernte_one]

hello Bernard

thanks for sharing your project
rights stuff for the rainy days here in germany

[bernte_one]

Hello Bernard,

i have build the Pickini V3 this weekend. Works ok, and i have adapted the layout to Sprint Layout. It was easier to handle for me than a black white picture.

So i can only say again thanks.

But there is still one question- i have proplem to find a good speaker for this project the one i have laying around here are not laud enough.
Best is Headphone for the moment.

Which Speaker did you use?

I also experimented with a lm386 amplifier and a little 8R speaker but it gets to fast unstable and noisy but was really loud.

A piezo dont work in this project. And the common speaker are not loud enough a 5V from µController.

Can you give me a tip?

[Toros]

Sorry, Eduardo, but I will not port the code to any other flavours of Microchip. I have done this in the past and although, they are all "alike" and pin compatible, there are some sneaky little differences in the internal resources and even differences in code.
There seem to be quite some Microchip distributors in Brasil and the 12F1840 is relatively new and widespread, so it should be possible to get some samples:
http://www.microchip.com/distributor...SA&terr=Brazil

Good luck,
- Bernard

Hi Bernard!
Does your words mean that for ver. 1(PIC 16F616) and ver. 2 (PIC 16F1824 ) we will not see corrected hex files without bugs.

[edu38]

Hi to all:
Bernte one can you upload the sprint layout converted file for board.....

Thanks in advance and congratulations again to author......

[sinclairuser]

Hi Bernard!
Does your words mean that for ver. 1(PIC 16F616) and ver. 2 (PIC 16F1824 ) we will not see corrected hex files without bugs.

why would he?, the new chip and code are upgrades, no one ever debugs obsolete versions, it makes the upgrades a pointless exercise,
you are supposed to build the new version.

[F117]

Does your words mean that for ver. 1(PIC 16F616) and ver. 2 (PIC 16F1824 ) we will not see corrected hex files without bugs.

I will update the V1/V2 hex files as soon as possible. As mentioned before, the bug in the code results in not seeing an update of the sensitivity when you turn up the potmeter slowly. When you change it quickly, it will take the updated value. I will try to update the V1/V2 code this week yet.

[Toros]

Thank you F-117!

[Toros]

why would he?, the new chip and code are upgrades, no one ever debugs obsolete versions, it makes the upgrades a pointless exercise,
you are supposed to build the new version.

Hi Sinclairuser!
I made both versions and I am pleased with the work of the detectors. The only thing I do not like is the sound with a frequency of 1 hertz, which shows that the detector works. I would like the sound to be heard every 10 or 20 seconds when to show that the detector works. To distinguish it from other signals sound can be a double pop of. This is my opinion, which do not require the author in any way.
Of course there is no difficulty from Eagle PCB file to make board by method "iron toner transfer", but I would like to have the updated hex files for ver. 1 and ver. 2.
I wish success to all who make ver. 3. Least I will later do ver. 3 and compare the performance of the detectors.

[sinclairuser]

Hi Sinclairuser!
I made both versions and I am pleased with the work of the detectors. The only thing I do not like is the sound with a frequency of 1 hertz, which shows that the detector works. I would like the sound to be heard every 10 or 20 seconds when to show that the detector works. To distinguish it from other signals sound can be a double pop of. This is my opinion, which do not require the author in any way.
Of course there is no difficulty from Eagle PCB file to make board by method "iron toner transfer", but I would like to have the updated hex files for ver. 1 and ver. 2.
I wish success to all who make ver. 3. Least I will later do ver. 3 and compare the performance of the detectors.

me too, sorry if my post came across as snotty that was not intended, it is unusuall for any developer either pro or hobbyist to "fix" previous versions, so i take my hat off to f117, those posters who asked about porting this version to the last chip can now rest easy, if ver 1+2 is going to be fixed, the there are plenty of options for builders who can only acquire previous chips, so a winner all round.