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Pin pointers electronics - need someone with good electrical knowledge
GoldPandemic  
Posted : Sunday, 7 August 2016 6:11:58 PM(UTC)
GoldPandemic

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First a quick question
Which type of detector requires motion to work Beat Frequency Oscillator or Pulse Induction?
(I thought it was Pulse Induction but have been reading conflicting information.)

I have some pinpointers that I've ripped apart.
The first is a Minelab Pro Find 25 the $300 kind.
The circuitry is small and complex, unfortunately this is no longer working as I dremelled the coil when removing the plastic case :\
And the case is gone to the recycling centre.
I can easily fix the coil though. This coil has thick wire and only one coil (I'll confirm that later).

Next is El Cheapo Chinese Ebay generic.
It still works, the circuitry is very simple. This has two coils.
I can easily provide a schematic of this.

I'd be happy to provide some pictures too.

What I want to know is if I play around with the coil windings & ferrite cores, can I damage the electronics?
Is there a limit on what these components (capacitors/transistors) can support - coil output range?
(I realise that will require some more detail on the components - let me know what you need and I can supply it).

Cheers in advance
Treasure/coins: $1
Other artifacts: 1888 button
Lead: 914g
Copper: 46
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nafcd  
Posted : Sunday, 7 August 2016 6:59:29 PM(UTC)
nafcd

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I have played a bit with these. not an expert but as far as I know if you alter the windings then transistors and possibly other parts need to be changed to suit. don't think it would blow up in your hands if you don't. lol. probably just wont work.
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GoldPandemic  
Posted : Monday, 8 August 2016 11:03:10 PM(UTC)
GoldPandemic

Rank: Gold Ingot

Medals: Donation: Made a donation helping cover the running costs of the site - thank you :)

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Was thanked: 141 time(s) in 102 post(s)
Thanks.
Well, seems my El Cheapo pointor doesn't use BFO, VLF or anything. Um it's some weird DC variance.
This video explains the entire circuitry. Think I'll have to investigate a different pointer.
https://www.youtube.com/watch?v=RqB93K47Phg

If anyone wants another look at it, this page has many circuit designs, and the one labelled MK II is the same design.
http://www.talkingelectr...rs/MetalDetectors-1.html
Oh any if anyone wants a detailed schematic, mine might be a bit more accurate that the video guys.
I held mine up to a light and could see 99% of the circuit paths.
Treasure/coins: $1
Other artifacts: 1888 button
Lead: 914g
Copper: 46
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