Can pinpointer detecting thin chain?

[Nupi]

Hi paku,

I do not understand your question. Can you extensive tell me what you meant?
You know my English is not the best at Geotech.

But much better than from Kt315.

Regards nupi.

[paku]

hello nupi which one you working schematic here!
i want try build this pinpointer

[Nupi]

Hi ToddB66
Nice that you're building and experimenting.

" I assume the tape you use allows the flux field from the wire coil to penetrate into the tri-core to help
amplify the pinpointer EMF and maximize signal distance". ????

I do not know where you got this information from but this is new to me.

The tape I use is masking tape, nothing special.

Do not use electrically conductive adhesive tape.

Regards nupi.

[ToddB66]

Can pinpointer detecting thin chain?

Hi nupi !

I am going to build a Velleman Metal Detector kit K7102 and morph it into a pinpointer, as you may have read on one of my previous posts.

It's taking me a very long time to get started into the build mode, but being an electronics newbie, I've been doing a lot of study to educate myself before starting. All my life I've been a perfectionist when it comes to building anything and I enjoy the research and gaining head knowledge before beginning a project. It's more satisfying for me that way.

I've noticed in previous photos of your tri-core electromagnetic pinpointer coil that you wrap the 3 iron cores with some type of tape. I assume the tape you use allows the flux field from the wire coil to penetrate into the tri-core to help amplify the pinpointer EMF and maximize signal distance (a mouth full, I know...sorry!). I would like to wrap the little iron core rod that came in the Velleman kit with an electrically conductive adhesive tape, to improve the ease of wrapping copper wire around the iron core nice and tight.

Would you mind telling me where I can buy an adhesive tape that does not act as an insulator (like some of the clear Scotch tape I have around the house does) ?

Thanks in advance for the help.

ToddB66

[moruka]

Hello, I also tried with a ferrite 10 mm. and the result is as dobar.Polimer-I am also Sea and noticed that PP is influenced by breath, but I think the problem is the thermal stability is influenced by T1 -zalyah it with silicone and now it will beep .Uspeh all. ..... For information -my coil wire 0.41 to 10 mm ferrite -layers(turns) are both scheme-NUPI and works perfectly.

[Funfinder]

The coil of the Pinpointer should have this shape:

and not that:

[Funfinder]

> That looks very good, and also waterproof, beautiful.
> The shape is almost the same as the previous PP. But why would you change, which is excellent!
> Do you know what it costs?

Nupi, your coil looks extremly good and its better because shorter and thicker than those of the Pro-Pointer!
Really very good. Perhaps you can use thinner wires to get even more windings and melt it into
some sort of plastic housing that is absolutly hard but still safe of fractions when in use -
there exists a huge variety of plastic from very cheap and easy destroyable to super solid.
Per instance that piece of plastic from the coil-cable-plug which contains all the connections is extremly solid.


The new waterproof thing of the Garrett Pro-Pointer is nothing special as long as they
don't use now a much better gum-part for the on-off switch.
Because before it also was already waterproof after glueing the beep-slots and a little bit
the region around the LED.

Guess I will not change because I'm pretty shure the critical-adjustment-screw-mod still will
give more sensitivity and also is much easier to use than this new 3 different sensitivity mode.

The tip of the PP still isn't "penetration-shaped" as it should and maybe its also still press-sensitive.
(if the coil plastic gets pressed, it starts already to give detection-signals, which it shouldn't)


The price - nuggets.at sells it for 150 Euros in one month - in the US it may costs around 170 Dollars.
btw. there's also available the new Makro Pointer for 109 Euro, waterproof and very sensitive, too.

http://www.nuggets.at/Makro-Detector-MakroPointer-Pin-Pointer-Metalldetektor

[Nupi]

@ Polymer

@ moruka

Once I experimented with epoxy, with good results.



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Regards, nupi.

[moruka]

I had the same problem with breath (warming) of capacitors.
After replacing with good MKP -stabilnostta available.
Thanks Nupi

[Polymer]

If you do not make good the coil may be that you are coming out of 100k
Khz area. I had better to advise 220k than 100k potentiometer.
But he now works.
Nice trip.
Regards, nupi

Hello Nupi,

I had a lovely trip thank you!

I didn't like reading that I might not have made a good coil, but I did listen and made a new one with a better winding technique.
Voila, it works much better and the adjustment to null is now at 76.4 kOhm in air. Putting the effort into making the coil
really well is definitely worth it. These values are for one ferrite rod (not three) and the detecting distance is still incredible.

Thought this might be of interest to other builders of electronic circuits:
I have had stability problems with the pinpointer which drove me nuts. Adjust to null, wait a few seconds and then it starts: bip, bipbip, bipbipbip more bips
and then it would slow down again. This happened quite often. Even the finest multiturn potis did not help.

I did find out what the problem was and you'll all be laughing or not believing it ...
Sooo, what was happening while I was testing the pinpointer on the table in front of me? Any wild guesses?

Well, it turned out to be my own breath .
Yes, my breath condensated on the circuit board and changed the resistances for a while.
I must say that I live close to the sea, there is always some salt in the air, it's humid and the houses are not heated
here in the short winter which translates to 15°C inside, where your breath will condensate on anything ...

Northern Europeans with cosy heating and very dry air will not have this problem I assume.

Anyway, I will be putting a coating on the pcb after finalizing the nupi pinpointer to prevent condensation quirkies.

With kind regards, Polmer

[Nupi]

That looks very good, and also waterproof, beautiful.
The shape is almost the same as the previous PP. But why would you change, which is excellent!
Do you know what it costs?

[Funfinder]

thx to you and the great constructive action, nupi.
btw. here's the brand-new coming soon Garrett Pro-Pointer AT - with 3 sensitivity levels:

http://www.garrett.com/hobbysite/hbby_pro-pointer_at_main.aspx

[Nupi]

Hi, Funfinder.

Thanks for your kind words, I appreciate that.

Regards, nupi.

[Nupi]

Hi, Moruka.

For the right point, you can adjust the resistance R1.
You can Nupi pp also adjust so that it works as an "off-resonance", if you prefer.
This is set using R2.
R1 used to adjust the threshold.

Thanks for your kind words.
good luck, nupi.

[moruka]

How many words
Already have termostabilost,C1 i C2 -culprit
should design housing