PICKINI V4 - an easy to build, self adjusting PI detector

[rodrigo_mattia]

Hello, Greetings from Brazil. One question, it is possible to use li ion battery pack with 4 x 18650 , and down the voltage with a 7812 before pickini board. Or is better that coil had feed direct from battery pack?

[popka-ru]

[popka-ru]

OK. we will adhere to your recommendations. just wanted to achieve the minimum size and weight. I plan to make a metal detector of this design.

[BC547]

No idea why you would want lower voltage ?
Most people use 3 x LiIon 16850 in series to achieve a 12V power supply.
Old laptops are a free source for these batteries - and they have plenty of capacity to search for many hours in a row without recharging.
Also lower voltage means less current through the coil.

The 6f22 9V blocks don't have enough capacity and too high impedance to deliver the current needed in a PI detector.

[popka-ru]

how to remove the voltage limit. that would work at least 7-8v and not from 10-12v? and then one battery 6f22 only lasts for 20 minutes and then does not work. is the detail responsible for the voltage limit?

[BC547]

The sensitivity potmeter can be 4K7 or 10K.

[popka-ru]

How much "KOM" should be a trimmer SENS? 10? 50? 100?

[BC547]

Another layout with the LM318 mask upside down. Pin 4 = GND.

[Alfredo Padrao]

I think this is correct

Is this layout with only PIC16F1824 smd available in sprint.lay or in pdf?

[BC547]

Upon general request: how to attach extra LEDs

- An extra LED to pin 7 = DETECT ON every time a target is detected. This is static high or low.
- Extra LED to the audio output pin 11 : when no target is detected, this LED will be 1 second ON and 1 second OFF ( 0.5 Hz)

[rodrigo_mattia]

Hi Popka-ru, I made this on my pickini v4 . I tried to draw it in the diagram.

https://photos.app.goo.gl/oBIr39HrqYDXkz3q2

[popka-ru]

better on the diagram show what and where. in words or what is not clear, especially if a foreigner

[BC547]

Nice video, Rodrigo.
No, the diode is not needed.
The Led is a diode.

[rodrigo_mattia]

I made a mistake , follow correct

1)to conect a led


Before c15


---resistor(1k)--(diode 1n4148 ) --led---to ground
|
--capacitor(c15)


Obs. Maybe the diode is not necessary, according F117

[BC547]

You should connect
the Led and 1k series resistor directly to the microcontroller pin, BEFORE the capacitor