SUPER D COIL

[dbanner]

If I can figure out a reasonably accurate method of winding an omega Tx coil for proper inductance, I would build more coils of the omega design.
There just simply is no good way of calculating the number of turns required without experimentation. A least I don't know of any.
The Magnum metal locator article describes a method of winding the coils for that particular project, but it does not specify any formula used to calculate the number of turns.

I built an omega coil and the performance was very good, and it is very easy to null correctly. I used it on an old bounty hunter TR circuit and it worked good.
But getting the number of turns of the Tx for such an odd shape is where the trouble starts. There is no coil calculator for this purpose.

This is one of the first coils I ever made. Omega design.

[godigit1]

It may not be totally accurate but on odd shaped coils I take a single wire and make one loop then shape the loop round to get a diameter from for the calculator.

[kt315]

just put cartoon or better film with graphite layer under the windings. do then in oldie tradition. always think about how to make anti ESFI protection.

[6666]

dbanner, when I was messing around with Reg's PI folded 8 coils, (see picture), I was amazed that starting from an 11 inch round coil, and folding it to an 8 the inductance 300uH did not change, so could be worth a try on omega. Measure odd shape with single wire, transfer to round coil, put into Q's calculator, wind or bend, I dunno just a thought

[dbanner]

Yeh, I think that some guesstimation would be required at first, just to get into the ball park. After some experiments and winding a few coils, you could easily begin to see how the omega shaped coil inductance would vary from a round coil of the same diameter. Then you would simply calculate the turns using round coil calculator and apply a correction factor to derive the turns for the omega. Simple really. So long as you have settled on the final omega shape though (some omega coils have larger feeback than others)

But back to the Super D!

[dbanner]

The omega Tx coil can be looked at as two separate coils. The Tx coil and second, the feedback. I suspect there will be a way to calculate the parameters.

[gurdal]

Hello,
Does the drawing have a CorelDRAW file?

Hi, no problem, dimensions in attachment, but... I do not count turns. I remember Tx was like 39-40, but Rx I do not know, between 170-180 turns, but I rather measure inductance. And I do not use the 328p tester which is in video, it measure inductance around 1mH well, but lies a lot around 14mH (it shows around 19mH on 14,7mH coil...). Use KT315 coil tester or plane oscilator and calculate inductance from known frequency and capacitor.

Good luck

EDIT: I believe I am 5 posts before GURU, could somebody please propose new avatar for me also

[Hyena]

Hello, only dwg or dxf, Ill check what format it is can be saved to. I think its so simple it should be matter if minutes to draw. If not... what formats you can read?

[gurdal]

dxf

[Hyena]

DOD pattern

With cover, enjoy...

[gurdal]

thank you so much

[gurdal]

Hi Hyena
How should DD coil value for idx pro be?

[Nandor]

Tx-should be the same 580uH~
Rx-2 identical coils with 17mH~

[gurdal]

hi

for information
thank you very much

[gurdal]

Hi
roughly metal detection beautiful.
I do the reset and fine-tune the test in the following days
Yours truly