Can pinpointer detecting thin chain?

[Funfinder]

For the ultimate sensitivity-test all you need is a teabag!

If your Pinpointer detects the 5mm iron clip it's really good!
The Garrett-Pro-Pointer only reacts if its modified and set to
highest sensitivity while directly touching the coil-housing.

[Nupi]

The ultimate teabag !?!



From what prehistoric country and year of birth are you my friend?

I have never in my life seen anything like this.

[Funfinder]

You are the profi - you have checked it perfectly!


The consumption-date was: best before 2011 !!!
See jpg!
You need 6 bags in 1 l. water for still getting some taste!

btw. the clips are already aluminium - said the magnet test.


Sorry, I don't drink much tea but herbs-liquor, its much healthier !!!

I can recommend Jaegermeister, Fernet, Ouzo, Raki and Mastika!

Just the best herbs there are inside and not like caffeine containing chai
which just makes everyone nervous, hyperactive, unruly and sleepless.

I hate coffee, tea and nicotine !! This is only cheap "opium for the people" -
seducing the mind so they are paralyzed enough for accepting every crap!
Most poeple take this as some sort of Red Bull or Coca to have enough power
for getting over the hard working day, but all this freaks up their brains, too!

Drinking tea is for old people to stay awake when death calls for: eternal sleep!

But if you'll wait 7 years until the caffeine is deactivated and everything tastes moldy,
you might can enjoy some interesting drink - if you use at least 6 tea-bags!

[Polymer]

Hello Polymer,

Sorry, for the late response.
It's not that I have no interest to answer your questions.
I have not received notice of Geotech that there was activity, or I have not seen it.
I always answer the questions they ask me or they must behave like *******s a**h***s.
I have not been on the "Thread: Can pinpointer detecting thin chain?" for a long time but often at the forum and have posted the necessary crap!!
So the next time if I do not answer within a week, please send me a personal message, okay?
To answer your first questio.
" I'm looking into how to deal with or counter the extreme temperature drift I have and find the main causes (Coil, ferrite, capacitors, transistor). @NUPI: can you offer some insights into this? ".
---- My first problem is that my electronics knowledge is not so big to explain clearly all the details.
---- My second problem, and probably the biggest, is that my English is
not so good to explain clearly all the details.
What I can say is that the oscillator is a derivative of a Hartley and that the coil is sensitive to temperature variations also because of the few turns which the coil counted.

But those who can explain more with certainty, the are the following persons:
Carl-NC, Teleno, Ferric Toes, Davor, Skippy, Dave J., Qiaozhi....................
There will certainly be more, but these are a few that come to mind I think that want to help you.

" Since this is not a publicly open forum, do you mind if I post your schematic with questions on an open electronics forum? "
I think that is fine, if you its origin mentioned. (http://www.geotech1.com/forums/showt...345#post224345)

P.S. I'm working on a new version of the PP in SMD pieces will be smaller and more stable.
Then I want to start the project VLF / IB M.D. for Geotech forum which will have the qualities of the previously described detectors that have been appointed / discussed in this forum. This is a big project and I need to have help. First to answer the questions in clear and good English, therwise it will be impossible to let it become a success. This is also how to continue my health.
Have a nice weekend.

Hello Nupi,

Thank You so much for your reply (dancing smily)
No worries about not seeing my post. I didn't want to be annoying by pm-ing, but may do so now

Anyway, it's nice to see the "black sheep" bright and shining!

I will be putting my collection of information & thoughts around temperature compensation here soon.

This is for me to focus this better, maybe see through the trees more and perhaps finding the easiest way to take care of this.
All this with your and others esteemed help I hope. I'd rather sort this out here with detector cracks than in some electronics forum.

I understand your english very well.

Gosh, an SMD version - please don't sneeze. You are brave! The thought of soldering SMD gives me nightmares.
I don't need NUPI PP smaller, but if it helps stability, I will have to face my bad dreams

Wishing You the greatest of health, Polymer

[Polymer]

NUPI PP thermal drift

I measured the needed adjustment of potentiometer R1 to get back to the tipping point in respect to temperature.
It's roughly +500 Ohms/°C with 3 ferrites in my setup.

I thought a simple linear ptc in series would do the trick and couldn't find one with such high ppm values.

Put many of them in series I thought. Aaah f**k, they combined have a much higher base value than the pot R1.
That path doesn't work here. So I dug a little deeper.

Here are some temperature basics I came across for the components involved:

Component change ppm/°C Values are not precise, ballpark figures (sorry about the formatting, can't get it to work properly)

Metal Film Resistor +- 50 to 100 (It's sort of a U-shaped curve)
Trimpot Cermet + few 100's
Copper wire (R) + 3900
Ferrite low f +500+- 100's
Ferrite high f +30 to 100
Transistor Si -3255 (or given as 2.1mV/°C) ???
MKP Capacitor (PP) -300
FKP2 Capacitor (PP) -200
Polyester Caps (PE) +200

Where to begin? I don't understand how the analog side NUPI PP really works, so I feel lost
at how to really go about this. Here's some other things that came up:

Since my NUPI PP beeps faster as the temperature rises I'm assuming that “C1 + C2” values are dropping,
causing the frequency to rise. A polyester cap might be better here instead of MKP,
if higher dielectric absorbtion is no issue. Is that line of thought correct?

The two "strongest" factors here appear to be the transistor & coil windings.
I have read that a matched transistor pair configured as a differential amplifier
can solve thermal drift problems (not perfectly, but substantially).
Could this be a feasable possibility within this circuit?

I may well be mistaken with my thoughts and it may be something completely different.

You are all welcome to give your input, corrections and insights.

[Nupi]

Hi, Polymer,

Watch your personal message.

[Funfinder]

Here's another test-object:

The "bolt"-region of a pulltab, 6x6 mm aluminium.

I've found it with the Makro Racer (standard coil) 50 meters from a highvoltage line -
5 cm grass & 5 cm buried. 3 meters away I've got the missing part of this thing, too.

The Garett-Pro-Pointer detects this 6 mm alusquare at 1 cm distance
normally, but already at 4 cm with modification set to high sensitivity.

Which means that the Pro-Pointer is pretty useless without modification
because if such a piece of metal is just 2cm away, the Garrett no longer
finds it !!!

And now we all wanna know from what distance the Nupi PP detects it!

[Nupi]

Here's another test-object:

The "bolt"-region of a pulltab, 6x6 mm aluminium.

I've found it with the Makro Racer (standard coil) 50 meters from a highvoltage line -
5 cm grass & 5 cm buried. 3 meters away I've got the missing part of this thing, too.

The Garett-Pro-Pointer detects this 6 mm alusquare at 1 cm distance
normally, but already at 4 cm with modification set to high sensitivity.

Which means that the Pro-Pointer is pretty useless without modification
because if such a piece of metal is just 2cm away, the Garrett no longer
finds it !!!

And now we all wanna know from what distance the Nupi PP detects it!

[ATTACH]38252[/ATTACH]

To perform properly the tests that you ask, we need more information from you.
You should at least share the following information with us.
.
COMPOSITION OF SOIL
-- The moisture content of the soil
Soil is a complex body composed of five major components (Fig. 1.3 namely:
----- mineral matter obtained by the distintergration and decomposition of rocks;
-----organic matter, obtained by the decay of plant residues, animal remains and microbial tissues;
-----water, obtained from the atmosphere and the reactions in soil (chemical, physical and microbial);
------air or gases, from atmosphere, reactions of roots, microbes and chemicals in the soil
-------organisms, both big (worms, insects) and small (microbes)
Classification of soil particles according to two systems (U.S.D.A and International)
Coarse sand, U.S. Dept. of Agric. system Diameter (mm).
----Very coarse sand,
----Coarse sand
----Medium sand
----Fine sand
----Very fine sand
-----Silt
-----Clay

Orders of soil (i.e. types):
Orders are the highest category of soil classification. Order types end in the letters sol. In the US classification system, there are 10 orders:
(1) Entisol - recently formed soils that lack well-developed horizons. Commonly found on unconsolidated sediments like sand, some have an A horizon on top of bedrock.
(2) Vertisol - inverted soils. They tend to swell when wet and shrink upon drying, often forming deep cracks that surface layers can fall into.
(3) Inceptisol - young soils. They have subsurface horizon formation but show little eluviation and illuviation.
(4) Aridisol - dry soils forming under desert conditions. They include nearly 20% of soils on Earth. Soil formation is slow, and accumulated organic matter is scarce. They may have subsurface zones (calcic horizons) where calcium carbonates have accumulated from percolating water. Many aridiso soils have well-developed Bt horizons showing clay movement from past periods of greater moisture.
(5) Mollisol - soft soils with very thick A horizons.
(6) Spodosol - soils produced by podsolization. They are typical soils of coniferous and deciduous forests in cooler climates.
(7) Alfisol - soils with aluminium and iron. They have horizons of clay accumulation, and form where there is enough moisture and warmth for at least three months of plant growth.
( Ultisol - soils that are heavily leached.
(9) Oxisol - soil with heavy oxide content.
(10) Histosol - organic soils.
Other order schemes may include:
(11)Andisols - volcanic soils, which tend to be high in glass content.
(12) Gelisols - permafrost soils.

......................."50 meters from a highvoltage line"................................
We need to know how high the magnetic fields are.
Magnetic fields are typically measured in tesla (T) or more commonly, in gauss (G) and milli gauss (mG). One tesla equals 10,000 gauss and one gauss equals 1,000 milli gauss.


............................"grass "................................................. .....
There are a multitude of grass varieties.
The grass family of plants is one of the most diverse, including more than 12,000 species.
The major difference among grasses is the type of photosynthetic pathways they use.
With more than 12,000 species, many very alike and many very different, we could discuss the varieties of grass indefinitely.
We need to know what kind of grass it is.


We need to identify the manufacturer of the Pulltap.
To mention some:

Anheuser-Busch Packaging Group/Metal Container Corporation
Ardagh Group
Ball Corporation
CROWN Holdings, Inc.
Silgan Containers LLC
Alcoa Inc.
Constellium
Novelis Inc.
Tri-Arrows Aluminum, Inc.
AkzoNobel Packaging Coatings
Domino North America
Eastman Chemical Company
GCP Applied Technologies
Henkel Corporation
INX International Ink Company
Materials Sciences Corporation
Mexichem Specialty Resins, Inc.
Pallcon Services Co, Ltd.
PPG Industries, Inc.
Roeslein & Associates
Samuel Strapping Systems
Signode Packaging Systems North America
Stolle Machinery
The Valspar Corporation
Watson Standard

But it seems easier that you make a Nupi pp and that you are testing by yourself.

[Qiaozhi]

Nice one Nupi!

Merry Christmas!

[Nupi]

Merry Christmas!

[Polymer]

Happy New Year Nupi! Better late than never ...

Here photos of ferrites I could not put in PM - Only the URL thing shows up there !??????.

[Virdi_248]

I give up. Two years ago I tried to make pp and it did not work. Now I have repeated the circuit in a perforated plate connecting everything as shown in the diagram and it does not work either. The only difference is c1 is mkt, I can not find it in mkp. Even if c1 mkt pp should give some signal? My pp is totally silent.

[ionut_mtb]

Need to be mkp. Try to put bigger trim pot for adjust.

[Virdi_248]

Need to be mkp. Try to put bigger trim pot for adjust.

Okay, I'll put bigger potentiometers.
Can I substitute c1 for 1.5n mkp? It's the one I can get in the store.

[Polymer]

Okay, I'll put bigger potentiometers.
Can I substitute c1 for 1.5n mkp? It's the one I can get in the store.

Like Ionut is saying try a bigger pot first. I understand your frustration, had that too. Wanted to smack it with a big hammer.

I use an approx. 70k fixed resistor in series with a 50k multiturn trimpot in series with a 2k multiturn trimpot (for fine tune).
Are you driving the speaker or LED directly from the 4024? For me this did not work well at all.

Is your coil wound correctly and have you connected it the right way around? Have you checked the voltages? Is your transistor in the right way?
My 3906 & BC560 have different CBE-EBC, so that could be a problem.

I am not sure about the 1.5nF capacitor. I will see if I have one and try it and post the result.

Could you put a photo in here? Good luck!