Can pinpointer detecting thin chain?

[Nupi]

I think with a proper integrator this whole thing should be possible to operate with virtually no tuning. Just turn it on and find some treasure.

Would you describe your idea in the circuit can you?
By the way, you've already had some time to try out the Colpitts in practice?

[Davor]

I think with a proper integrator this whole thing should be possible to operate with virtually no tuning. Just turn it on and find some treasure.

[Nupi]

That is interesting idea with sliding magnet.
Probably more easy is to use Reed switch to turn power with same magnet. Approx $0.50 or cheaper on eBay.

[ATTACH]29179[/ATTACH]

And for tune with same sliding (or rotating) magnet there is a Hall Effect Sensor A1301 which can provide voltage output proportional to magnetic field strength:
http://www.allegromicro.com/~/media/Files/Datasheets/A1301-2-Datasheet.ashx
Only a problem is that Hall sensor voltage have to be converted somehow to manipulate resistance of R1 with it.

Nice idea with the Hall Effect sensor. Maybe it's just too difficult for a simple pinpointer.
Waikiki I know you have several good ideas. Tell us more.

Come on people, this is an open thread, where are the other ideas???

[Waikiki_Sweep]

A suggestion for a waterproof pinpointer.

That is interesting idea with sliding magnet.
Probably more easy is to use Reed switch to turn power with same magnet. Approx $0.50 or cheaper on eBay.



And for tune with same sliding (or rotating) magnet there is a Hall Effect Sensor A1301 which can provide voltage output proportional to magnetic field strength:
http://www.allegromicro.com/~/media/Files/Datasheets/A1301-2-Datasheet.ashx
Only a problem is that Hall sensor voltage have to be converted somehow to manipulate resistance of R1 with it.

[Nupi]

You are rigth
My VRT show´s bottom view (but barelly visible)

I have that problem sometimes with the data from books.
I am looking now mostly these in Google Images.
And compare several images.
Who is most common is usually the proper.

[Nezocas]

BC560 front view CBE
2N3906 front view EBC

You are rigth
My VRT show´s bottom view (but barelly visible)

[Nezocas]

My best results so far has been with the BC560C.

Thank you so much

[Nupi]

Hi,

One more question
Which transistor was used in TR1

My VRT2009 show´s this:

BC560 front view EBC
2N3906 front view CBE

Regards

Hi,
My best results so far has been with the BC560C.
BC560 front view CBE
2N3906 front view EBC
they are both PNP trans.

[Nezocas]

Hi,

One more question
Which transistor was used in TR1

My VRT2009 show´s this:

BC560 front view EBC
2N3906 front view CBE

Regards

[Nupi]

I need low tide to go far away from the beach. Often good tide is at night so I have wait for it. Intersting that even at 4 A.M. you can see a few guys with metal detectors here. I was surprised once starting at 4 A.M. because of best tide of the day falls on that time and see beach crowded with metal detectorists at such a deep night.

Also at night you can met all that ocean night life creatures: sea turtles, sharks, octopuses, ills, stingrays.

I have installed LED light into my headphones and powered it from detector batteries so everything is waterproof and very convenient.
I have no idea why detectors manufacturers not adding night light functionality into their product.
Even iPhone has night light.

If some one wants such feature I can explain how to build it easily:

I am using coiled phone cord to connect my homemade waterproofed headphones.
In phone cord you can find four wires. For example I have used green and yellow as stereo output to speakers, black as ground, red as +12V to power LED light. Easy to remember.
On eBay you can find 10W white LED for $1,66. It is too powerful but you do not need to run it in full capacity. Just put proper resistor like 50 Ohm and it will runs perfectly providing 0.5-1W from 12V batteries inside your detector.
I am potting LED in clear epoxy preferably making diffuser around it to reflect light forward. Before I have used aluminum foil but it corrodes fast so now I just painting reflector surface by white paint. Easy to build and it is waterproof.
How to make waterproofed switch to turn it on? Easy. Reed swtich potted in epoxy and small magnet on plastic leverage. I am installing Reed switch on the top of "S" shaft and magnet turning it on with setup similar to trigger on gun.

That's a clever design, the reed switch and the light.
You would also be able to apply to the pinpointer if you want to make it waterproof.
You do not necessarily need a pot on the outside.
You can make the fine tuning on the outside.
You can create a slider with on-off switch with a magnet and mini-switch.
The sensitivity set you with the same slide.
There are of course several solutions imaginable.

In order to operate the pinpointer fully automatic we need more go direction
Davor or another genius.
I'm not so far yet, and at my age it will not happen, I think.
I am a practical man as occasional have a applicable hallucination.

A suggestion for a waterproof pinpointer.

[Waikiki_Sweep]

You're looking in the night? That's interesting. Do you do that because there is no more people swim?

I need low tide to go far away from the beach. Often good tide is at night so I have wait for it. Intersting that even at 4 A.M. you can see a few guys with metal detectors here. I was surprised once starting at 4 A.M. because of best tide of the day falls on that time and see beach crowded with metal detectorists at such a deep night.

Also at night you can met all that ocean night life creatures: sea turtles, sharks, octopuses, ills, stingrays.

I have installed LED light into my headphones and powered it from detector batteries so everything is waterproof and very convenient.
I have no idea why detectors manufacturers not adding night light functionality into their product.
Even iPhone has night light.

If some one wants such feature I can explain how to build it easily:

I am using coiled phone cord to connect my homemade waterproofed headphones.
In phone cord you can find four wires. For example I have used green and yellow as stereo output to speakers, black as ground, red as +12V to power LED light. Easy to remember.
On eBay you can find 10W white LED for $1,66. It is too powerful but you do not need to run it in full capacity. Just put proper resistor like 50 Ohm and it will runs perfectly providing 0.5-1W from 12V batteries inside your detector.
I am potting LED in clear epoxy preferably making diffuser around it to reflect light forward. Before I have used aluminum foil but it corrodes fast so now I just painting reflector surface by white paint. Easy to build and it is waterproof.
How to make waterproofed switch to turn it on? Easy. Reed swtich potted in epoxy and small magnet on plastic leverage. I am installing Reed switch on the top of "S" shaft and magnet turning it on with setup similar to trigger on gun.

[Waikiki_Sweep]

It's a good Idea, in my opinion, I checked a circular board with the circuit, it would be +/- 38mm or around 1.5", less if stacked. The power could be a problem.

I think power should be in separate box or you can load it from your detector. For example I have used one set of Li-Ion rechargeables in my SurfPI to power up a detector + night light + mp3 player + audio amplifier.
Also all indication (LED,BUZ,MOTOR) may be installed away in box with power or detector case.

So you will need only 3 wires to connect sensor: "V+", "Ground", "Output to indication".

Only a problem with pots. They are not waterproof and you need assess to it. I am waiting for auto tuning schematic without pots, like motion detectors working with SAT, it would be great!

[Thomas]

Also I have an idea how to make it compact.
As I already have told frequently with bigger diameter core that pinpointer will go deeper - MORE LONG RANGE.

So I think it is reasonable to get a ferrite ring or cup big enough to put SMD PCB inside and wind coils outside.
So you will have a perfect slim disk working as sensor for pinpointer. Pot it in epoxy. All indications and power supply put on other side of three wire cable.

Now you can attach that sensor disk to your metal detector coil (with some spacing), or scoop, or boot and hook indication block on your belt or headphones.
So there is no needs anymore to hold pinpointer in hand (or use tail )

It's a good Idea, in my opinion, I checked a circular board with the circuit, it would be +/- 38mm or around 1.5", less if stacked. The power could be a problem.

[Nupi]

I bet you have a party all night before assembling that circuit. Try one more time when ready.

I not had a party.
I was with my dog. He's back!!

[Nupi]

It is sea turtle. I almost broke my coil several times hitting them at night when they crossing my way invisible in water.
Do not worry, my coil is so thin and light and they have very good armor.

I have some photos viewed But You live in a paradise.
You're looking in the night? That's interesting. Do you do that because there is no more people swim?
Interesting life you have. (I think)
Maybe I want to be your friend.