Help to design a PCB for my PI design!

[Unregistered]

tp= r12 trim.

r12 trim.= 0 volt

[Tinkerer]

I could ... but it may take a long time, due to other commitments.
If you email the design to me, I can pick at it during any spare moments.

Thanks for the kind offer. Time? I have been tinkering a few years with this, I guess as long as I am still tinkering I am still alive.
I will send you a design.

Tinkerer

[Rov]

This is a very good project!are the files from Qiaozhi suitable for a pcb manufacturer suitable to make a one off hobby pcb for me,like gerber?What should I do!
I have bought a small quantity of Atmega8 chips an a educational board to experiment an program.I am Looking forward to this ,is very good Project.

[Vermeer111]

ok i have one question,if i use the coil from the hammerhead detector is the damping resistor the same ? (680 ohms) i need this detector for coin relict and jewelery(rings chains etc) excuse my english Thank you

[1843]

ok i have one question,if i use the coil from the hammerhead detector is the damping resistor the same ? (680 ohms) i need this detector for coin relict and jewelery(rings chains etc) excuse my english Thank you

I think a higher value resistor should work. Do you have an oscilloscope? If so try 1K, 820R,...
680R certainly works OK, but not optimum.

[Vermeer111]

i don´t have an oszilloskope (in the moment) ok i will try 680 ohm with the coil for hammerhead Thank you for your answer

[1843]

New Hex

About the trimpots:

R26: Hold S5 and then switch the detector on. Now the detector is in battery adjustment mode and showing a number. Apply your minimum battery voltage (10 to 11V) to it, adjust R26 until the number is around 660.

R12: With a coil connected, temporary short the Base of Q9 to 0V. By adjusting R12 you should have a voltage of about 200mV at the pin6 of U7.

New Hex is attached. I've forgotten to reverse the backlight pulses in the previous revision.

[okantex]

Hi 1843 ,

since you have completed your detector.
what abuot coin test?? can you try few metals and share results with us.
may be a video presentation?

regards
Okantex

[1843]

Hi Okan,
PI-111 intently is designed for gold hunting. As I remember the detection depth for a hammer was the same for a gold ring!
This PI can detect a 1g gold ring at 8" using a 3" coil. I haven't tried larger coils...

[1843]

what abuot coin test?? can you try few metals and share results with us.

Why don't you build one to see the results by yourself?
It's very simple, cheap, easy...

may be a video presentation?

Are you doubtful? If so, Why? Do the risk to build this PI!

[okantex]

Dear ,
I am not interested in coin hunting , beach hunting .

[1843]

Adjusting

R12: With a coil connected, temporary short the Base of Q9 to 0V. By adjusting R12 you should have a voltage of about 200mV at the pin6 of U7.

And you also need to open R28, Otherwise the DC converter will stop pumping. Of course this procedure is needed for those who don't have an oscilloscope.

It's convenient by an oscilloscope:


Best regards,
1843

[okantex]

why there is no result of constructions?

could nobody succeed it yet?is something wrong with this projects.

why there is no video ,or pictures form working stuffs.or any test results?

regards
Okantex

[Fred]

Probably because there is many talkers and no builder...

[okantex]

Just wonder response of this design to
1. any coin or ring by approximately 20cm (diameter) mono-coil
2. coke or beer can by 40-60 cm (diameter ) mono-coil


regards