2 boxxxx :)

[chemelec]

Hi Chemelec,
what is the value of ?pF
and also coil size ,turn and wire number
type of buzzer ,and other construction parameters

could you add them to your page ,please?
and did you have any experiment with it.
about depth.
as he says detectoman 's serzirfo gets signal from 4 meters in-air
We wonders yours?
have a nice day

I Got Side-tracked on a bunch of other projects.
Is going to be awhile before I get back to this project.
Also, Spring is Coming. Thats Garden Time.
In June, I'm off to Egypt, Italy, Switzerland, France and England on a Holiday.

?PF is a Possible Additional Trim Cap to balance the Frequency between the recieve and transmit. It May or May Not be Needed.

Coil size is up to you. But I suggest you make them close to that Inductance Value.

Gary

[okantex]

Hi Chemelec
is that possible for you to make an experiment with your ferrite coils for us?
do you remember your ferrite coils that you give link in coils page.
with this two box circuits could you use number 3 and number 4.
as transmitter;
number 4 ,but on iron core (something like iron sweeper sticks,inside must be empty to have good wave consantration.)something like 2cm diameter and 3cm lenght will be fine.to increase inductance additional second circular coil in diameter of 5cm will be added in series.
as reciever;
number 3 , two u cores as I draw(sorry I could not copy it here .but you can see it inpage 2 of two box thread.the fourth one.)this is very stable winding for directional recieving.four legs must have same number of turns.it is in a way four windings in series.
as result transmitter coils will be between two u core.
How ?I do not know but this system enables to discriminate silver ,gold,copper,lead .,iron.
my old machine was using2.7pFcapasitors and 10 mF s
maybe small magnetic fields can reflect easyly and can get by this reciever.
because total (transmitter and reciver unit )unit 's size is two ciggarette packet one on other.
waiting for your positive steps
have a nice day

[chemelec]

Yes on these cores, I understand that much.
But on What detector?

but on iron core (something like iron sweeper sticks

I have no idea what you mean by this.
And there are Many types of Iron cores with many different Magnetic properties.

How ?I do not know but this system enables to discriminate silver ,gold,copper,lead .,iron.

OK, But What type of Detector was that?

Gary

Hi Chemelec
is that possible for you to make an experiment with your ferrite coils for us?
do you remember your ferrite coils that you give link in coils page.
with this two box circuits could you use number 3 and number 4.
as transmitter;
number 4 ,but on iron core (something like iron sweeper sticks,inside must be empty to have good wave consantration.)something like 2cm diameter and 3cm lenght will be fine.to increase inductance additional second circular coil in diameter of 5cm will be added in series.
as reciever;
number 3 , two u cores as I draw(sorry I could not copy it here .but you can see it inpage 2 of two box thread.the fourth one.)this is very stable winding for directional recieving.four legs must have same number of turns.it is in a way four windings in series.
as result transmitter coils will be between two u core.
How ?I do not know but this system enables to discriminate silver ,gold,copper,lead .,iron.
my old machine was using2.7pFcapasitors and 10 mF s
maybe small magnetic fields can reflect easyly and can get by this reciever.
because total (transmitter and reciver unit )unit 's size is two ciggarette packet one on other.
waiting for your positive steps
have a nice day

[okantex]

Hi Chemelec
loook at first page of this thread.there you will see drawing of whole unit.
it consist of two parts.one look like detector which is used by explorer who walks around the field.second is analyzer unit which is used by second person and no need to motion.when first parts walks on mineral or metal object ,the buzzer next to second man starts beeping.and he starts using analyzer.
I tried to write the writing at the back of analyzaer.
but this is not an trade mark.it was made special for mining company who works in asia at 75's(1975).
so I can not able to give you a name for a detector.in my opinion this is more than a detector.
for iron core.
think some thing like pipe.at diameter of 2cm and cut it at lenght ıof 3cm.this is the core.
I prefer to cut it from iron sweeper sticks.it is for collecting magnetic fluxes.
we have to adjust L value by usiing L meter.
thanks for attention

[chemelec]

Hi Chemelec
loook at first page of this thread.there you will see drawing of whole unit.
it consist of two parts.one look like detector which is used by explorer who walks around the field.second is analyzer unit which is used by second person and no need to motion.when first parts walks on mineral or metal object ,the buzzer next to second man starts beeping.and he starts using analyzer.
I tried to write the writing at the back of analyzaer.
but this is not an trade mark.it was made special for mining company who works in asia at 75's(1975).
so I can not able to give you a name for a detector.in my opinion this is more than a detector.
for iron core.
think some thing like pipe.at diameter of 2cm and cut it at lenght ıof 3cm.this is the core.
I prefer to cut it from iron sweeper sticks.it is for collecting magnetic fluxes.
we have to adjust L value by usiing L meter.
thanks for attention

Well I don't have that detector unit, So I really don't understand What you want me to do or try to test.
I Also DON'T have any "Iron Sweeper Sticks. I don't even know what they are.

Gary

[okantex]

it seems like I will try it own.but I do not know how I will wind them in correct inductance.I do not have L meter.

thanks

[chemelec]

it seems like I will try it own.but I do not know how I will wind them in correct inductance.I do not have L meter.

thanks

Do you have a Scope and Frequency generator?

You can determine the inductance that way.

[okantex]

Hi
no I do not have scope and oyher.
I tried to calculate number of turns for u core with Al value 2400nH according to information at your site.
you can see it at
http://www.aet.com.pl/en/ferryt/rdzenie_u3.html
but I found something like 1000 turns .there must be something wrong with it.because your u core looks like it has smaller number of turns.
thanks

[Qiaozhi]

Broken Link

Hi
no I do not have scope and oyher.
I tried to calculate number of turns for u core with Al value 2400nH according to information at your site.
you can see it at
http://www.aet.com.pl/en/ferryt/rdzenie_u3.html
but I found something like 1000 turns .there must be something wrong with it.because your u core looks like it has smaller number of turns.
thanks

The link you have provided is broken.

[Qiaozhi]

Now its not broken ?????

The link you have provided is broken.

I tried this link several times - and suddenly its working !!
Oh well... :confused:

[chemelec]

Hi
no I do not have scope and oyher.
I tried to calculate number of turns for u core with Al value 2400nH according to information at your site.
you can see it at
http://www.aet.com.pl/en/ferryt/rdzenie_u3.html
but I found something like 1000 turns .there must be something wrong with it.because your u core looks like it has smaller number of turns.
thanks

I have no idea What that U Core you have, really is.
I am also Not Familiar with that Manufacturer or that F827 Material.

There are Thousands of Different U Cores that may All look the same but have Different AL Values and Many Other Different Properities.

Some are for Power, Some for RF and others Various Frequencies ranges.

Looks: Doesn't mean Anything.

Those Formulas are Correct.

But maybe its time you bought some equipment to do some basic measurements.
A Scope and a Signal Generator would be a good start.

[okantex]

Hi Chemelec

what is the AL value of your u-core as you mentioned third bobbin in picture.
and could you show how to calculate number of turns step by step here.
Thanks

[chemelec]

Hi Chemelec

what is the AL value of your u-core as you mentioned third bobbin in picture.
and could you show how to calculate number of turns step by step here.
Thanks

That U Core is a "Fair-Rite" Part Number 9277012002 and it has an Al Value of 1625.
It Material 77 which is a Low Loss, Power Ferrite material.

Now as to the rest of your question: Sorry, I didn't use any calculation to Pre-determine the inductance of this coil. I didn't even bother to count how many turns. Alhough I knew from Previous experience with this U-Core, Aproximately how many turns were required to get within a ball park of what I wanted.

The Nylon Bobbins were also Custom made by me on my metal laithe, so they would fit an appropriate amount of turns when filled up.

My only purpose of these tests was to determine radiation patterns from the magnetic fields of Various Syles.
So the actual, inductance was arbitrary. Although I did measure them on my equipment at the time.

Since I Completed those tests, I have Disposed of those coils. So I can't go back to actually count the turns and do those calculations for you.

Possibly I could do another coil with calculations and Tested Results for you.
Would that Help?

Gary

[chemelec]

Hi Chemelec

what is the AL value of your u-core as you mentioned third bobbin in picture.
and could you show how to calculate number of turns step by step here.
Thanks

Something else you Might not be Aware of:

The manufacturers Posted "AL Value" of U-Cores: Is based on Two U-Cores put tightly Together to make a rectangle or square.
The Same goes for Pot Cores, two halves to make a closed cup.

Each U or Each side of a Pot Core is Only HALF of a Complete core.
And quite often they are sold as Sets.

The AL Value is for a Complete Core, without Any gap beween the two.
Adding a gap, decreases the AL Value.

Ferrites and there formulas can get VERY Complicated to work with.

Gary

[chemelec]

Here is a More Simple Example, using a: Fair-Rite Slug #4077375211

The Manufacturer: Fair-Rite does not tell you the AL Value of this core.

But here is how it is calculated.

Also an example of using this "Calculated AL value" to now calculate another coil that might be wanted.

Hope this Helps.......Gary