Simplest PI detector possible?

[bernte_one]

hello farafero

video(site) is not good for showing does not play or with long loading time
can you upload at youtube? or myvideo or so

you can also upload somewhere in cloud storage and i would upload it at at youtube if you give me a link for online storage

regards bernd

[farafero]

http://www.youtube.com/watch?v=fmx55...iaxEHRwvVa9SJA
or http://dox.bg/files/dw?a=36aed63f6a

[farafero]

I put a screen protective film for transformers 2 layers. I put Foley. The effect is the same, it reacts to the land.

[Waikiki_Sweep]

I put a screen protective film for transformers 2 layers. I put Foley. The effect is the same, it reacts to the land.

I have two versions: 1. Shield does not working properly. 2. Ground has enough mineralization to make a signal.

1. Check if your shield is it connected to "+". If shield works you will have no reaction when you touching coil by hand. Also you can use a wet towel to touch the coil. If no reaction than shield works good.

2. Regarding mineralization in your ground. If your detector reacting on ground but not reacting on sand than ground is a problem. Try to put it on ground than adjust settings to null the signal from ground.

Also this is simplest schematic that has no any ground balancing. If you will assemble for example Surf PI it may works a little better because it has two samples one for target and one for ground and it will compensate
ground signal. For really heavily mineralization ground more complicated detectors are used with more samples and really good ground balancing algorithms.

[jeohunter]

how much detech a coin test on air and below terrain ?

[farafero]

air 5 kopecks 20 cm in soil 8-10 cm

[jeohunter]

mm size of 5 kopecks ?

[farafero]

25 millimeter coin
in my video u can look
http://www.youtube.com/watch?v=fmx55...iaxEHRwvVa9SJA

[jeohunter]

tanks for show me video,
it is made from you on barracuda bases?

compliments

stefano

[farafero]

not a barracuda, this is a Russian pirate
http://radioskot.ru/publ/metalloiskatel_pirat/1-1-0-480

[jeohunter]

ok tanks

[farafero]

I found after many tests that shielding of this machine does not help in any case

[jeohunter]

shielding is important, to prevent faulse signals,
both the control units and both the coil,
open some commercial machine so you see whow are connect the scields

[Waikiki_Sweep]

I found after many tests that shielding of this machine does not help in any case

PI detectors at the moment of coil discharge generating fly-back - high voltage spike 80-600v.
As result their coils have electrostatic charge and capacitive coupling to the ground.
If detector coil has no shield or bad shielding it has to react on ground, water, wet sand, grass, ... any environment that conduct electricity.

Properly build and properly connected shield is a "Faraday cage" which is grounding any electrostatic discharge and coil windings will stop to create capacitor with conductive environment.

Also remember if there is no gap in shield it acts like target or shorting coil.

[jeohunter]

hello, i see you are expert, and me i am looking for a good technician higt level of experience, for project a professional and
power metal detector for me. someone for this interest is welcome, have good day, steve