TESORO GOLDEN SABRE

[ivconic]

Yes, you are probably right.
Nice software that!
Why dont you make trial and share here with us, just in tetsing purposes.
Regards!

[Aziz]

Yes, you are probably right.
Nice software that!
Why dont you make trial and share here with us, just in tetsing purposes.
Regards!

Due to patent opportunity, I do not want, that somebody finds a patentable coil. So I can ensure that the results can be shared here, without patenting.


Anyway, the software is not yet finished. But probably (hopefully) I will get many surprises and results with that in the future. I will inform you then.
Aziz

[WM6]

Anyway, the software is not yet finished. But probably (hopefully) I will get many surprises and results with that in the future. I will inform you then.
Aziz

Excellent work aziz. Very interesting output.
Can you processing some different shape of Omega coil?
Mean "omega" solution attached below:
"Overlapping" / tunning TX loop are not fully TX wound, it consist of only every third or fourth turn of TX coil.

]

[Aziz]

Hi WM6,

Excellent work aziz. Very interesting output.
Can you processing some different shape of Omega coil?
Mean "omega" solution attached below:
"Overlapping" / tunning TX loop are not fully TX wound, it consist of only every third or fourth turn of TX coil.

]

Generally, it is possible, also the nulling (balancing) of the RX-coil. But I can't read, understand and interpret the schematic above. Can you explain or show me a bit exactly?
I need the number of turns (such as 1 turn, 10 turn, 1/3 turn (referred to one for instance), etc.) of each coil. How they are connected (serial / parallel). Resistance of the coils (for current driving). Geometry data (position, radius, etc.).

It is not easy to put all the input data to the machine. I am sorry about, that my computer does not understand my speak. Remember Scotty on Star Trek: " Hello Computer! Computer? Computer??? "
Aziz

[Max]

Let's back to main subject here;
i am just making omega coil for TGSL. TX is 21cm and rx 10.5mm. Wire is 0.25mm. I wounded 98 windings for TX and 167 wind. for RX. I founded those numbers exact to suit needed inductances: 6mH (TX) and 6.5mH (TX).
Coil is not finished yet.Tomorrow i will apply f.cage (Al foil) and perform nulling. Later i will test it with TGSL to see performances....and of course report here...

Hi Ivconic,
nice to hear you are on the way with new coil for TGS! This time omega one ! Cool!

Why so small ? Just a trial ? 21cm round is good for e.g. trashy sites and with extremely precision pinpointing... but I think it cannot compete with your older large DD on depth sector.

I think a good one will be in the 10'' range... so about 25cm external round TX. This could match DD performances and also give better than before , with lose of widescan but much better pinpointing.

What do you think ?

Kind regards,
Max

[WM6]

Hi WM6,
Generally, it is possible, also the nulling (balancing) of the RX-coil. But I can't read, understand and interpret the schematic above. Can you explain or show me a bit exactly?
Aziz

Yes, Aziz, seems a bit complicated but is not, i hope.
Here is starting sketch to help you understand principle.
Thru tunning loop past only 1/3 or 1/4 of selected TX signal power.
All others can be the same data as you put in your last omega space visualisation.

[Aziz]

Yes, Aziz, seems a bit complicated but is not, i hope.
Here is starting sketch to help you understand principle.
Thru tunning loop past only 1/3 or 1/4 of selected TX signal power.
All others can be the same data as you put in your last omega space visualisation.

Ok, I think, I understand you now. The transmit coil is a one wire with x length, that is wound. It has a beginning and ending point, where the signal power is feeded (current I). The current is the same through the tx coils. But the number of windings of the inner tx-coil differs (e.g. every 3.rd winding, you go to inner coil and back).
The balance is made by changing (increasing) the flux area of the inner tx-coil (there and back area of the winding). If the flux area is zero (not the circle flux), the inner tx-coil does not induce magnetic field.

Ok, this is possible. But I have to make some simplifications. The connection between the inner and outer coil can be neglected, if they are close together. The inner coil can be made of some partial elliptical coils without rounding corner. This complex type of coils is not implemented and therefore the simplification is needed. Anyway the result will be almost the same as for ideal model.

I will try this. When I have understood wrong, then correct me please.
Aziz

[WM6]

I will try this. When I have understood wrong, then correct me please.
Aziz

Hi Aziz, I think we are close to basic idea.
Must be very artistic to simulate this.
Maybe only this addition about balancing/tunning:

[Fred]

Interesting coil!
80% concentric, 20% Omega.
If you read the PDF file about coils on the mainpages,you find that concentric coils also use part of windings for nulling.Similar i think.
Regards,
Fred.

[ivconic]

OK, i got first,preliminary results;
first i have to say, nulling omega coil turned to be much
more difficult than DD coil???!
(Last time i made omega coil was for MD3007 and i didnt used
present method by measuring induced voltage in RX coil)
It need 1/10mm to drop to 0 volts or to jump to 20-30mV!!!??
After much effort somehow i managed to achieve excellent null.
At 200mV range it says 0.01...more than good!
OK, than i resoldered RX wires from miliviltmeter to TGSL.
WOW! What a stabillity!!! I dont beleive my eyes!!!
It is very,very stabile coil!!!! Superb over DD coil!!!
Discrimination is P E R F E C T !!! Perfec,perfect!!!!
Ferrite rod is absolutelly invisible for this coil even if i
lower GEB trimer much "down" from usuall value, usually trimmed
with DD coil.... Usually, when DD coil nulled well, there are some
mum "cracks" on ferrite rod with trimmer on 60%. I usually left that
way and later turns detector acts pretty well on soil.
But now, with this coil - not "cracks" at all! Trimmer at half - no
"cracks". Thin silver coin - yes, detected loud and clear!
Wow.
Ok, depth is lower than 27cm coil. 1 Euro coin detects very easy at 24cm
in air. 1.5cm nickel coin at 28cm.
Considering diammeter of this omega coil - 21cm, i think it is not
shallow comparing 27cm DD coil, not at all.
Next thing i'll do is to make 27cm Omega coil and than see real differences.
Bit now, i left out of wire, so this will wait for week or more.
But discrimination is really perfect. Large iron claws - absolutelly invisible
in disc mode.
What to say more? Need to finish it and than perform full test outdoor on the
real field.
Until than...


Regards Max!

[WM6]

OK
What to say more? Need to finish it and than perform full test outdoor on the
real field.
Until than...

Congratulation ivconic. Now still field test, wider coil and then mass production. Good job, really!

[WM6]

Hi Aziz, I think we are close to basic idea.
Must be very artistic to simulate this.
Maybe only this addition about balancing/tunning:

Aziz missing sketch:

[Aziz]

WM6,

Thanks, I missed the graph to check the model. By the way, the computer model is done. I found that the proposal coil design above can not be nulled. The inner TX coil has to be on opposite direction to the outer TX coil. It does not matter. I will explain on some impressive graphics why this model does not work. But it will work on opposite current direction. Also the one third winding factor will very likely not enough to get nulled.

May be I should post the comprehensive results on the coil section to not disturbing the other contributors here. Please make a starting thread and I will post every step consequently. So at the and, we can make a prototype of nulled "Omega-concentric" coil. (How should we name this type of coil?)

Aziz

[ivconic]

Hi Ivconic,
nice to hear you are on the way with new coil for TGS! This time omega one ! Cool!

Why so small ? Just a trial ? 21cm round is good for e.g. trashy sites and with extremely precision pinpointing... but I think it cannot compete with your older large DD on depth sector.

I think a good one will be in the 10'' range... so about 25cm external round TX. This could match DD performances and also give better than before , with lose of widescan but much better pinpointing.

What do you think ?

Kind regards,
Max

Yes, it started as trial coil and turned to very serious ideas to adopt this as main type of coil for TGSL....
I didnt expected such good results at all!?
Most important fact is that this omega coil is indeed stabile as a rock.
I will repeat, it is very hard to balance it. Much harder than usuall dd coils.
But once it is nulled, well...well...
It think it will beat DD coil in depth also.
Not to mention narrowed area of detection.Pinpointing is 100% accurate with it. Actually area of detection is exact area covered by RX coil, no more, no less. In the past i made 2-3 omega coils for that md 3007, which was nomotion metal detector, poor performances comparing to TGSL. I didnt payed much of attention on those omega coils at the time. Those were made just to test detector, since original coil came with it was omega coil. I made few copies of md 3007 and logically made also coils for those by copying original coil. So i burried in my mind those as not so serious coils.
Now, i am equiped with more experience and payed a lot of attention on balancing and remaining exact inductances needed by TGSL.
I think i will propbably switch to this kind of coils in future. Yes next would be larger omega coil, at least 25-27cm. Huh, it will need further calculations and experiments to find exact number of turns for coils.
This time 0.25mm wire is used. On larger coil i guess 0.3mm would be more suitable to be used.
We will see...

[Aziz]

...Huh, it will need further calculations and experiments to find exact number of turns for coils.

Just call me! And you will save time and money!

This is a good job for my coil software.